I feel as if I have tried everything, but I am still unable to automate the process of joining a workstation to my domain using autounattend.xml. Below is a sample of my xml file. If anyone is able to figure out what I am doing wrong I will be forever greatful!

<?xml version="1.0" encoding="utf-8"?>
<unattend xmlns="urn:schemas-microsoft-com:unattend">
    <settings pass="oobeSystem">
        <component name="Microsoft-Windows-Shell-Setup" processorArchitecture="x86" publicKeyToken="31bf3856ad364e35" language="neutral" versionScope="nonSxS" xmlns:wcm="http://schemas.microsoft.com/WMIConfig/2002/State" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
            <OOBE>
                <HideEULAPage>true</HideEULAPage>
                <ProtectYourPC>2</ProtectYourPC>
                <SkipUserOOBE>true</SkipUserOOBE>
                <NetworkLocation>Work</NetworkLocation>
            </OOBE>
            <UserAccounts>
                <LocalAccounts>
                    <LocalAccount wcm:action="add">
                        <Password>
                            <Value>password</Value>
                            <PlainText>true</PlainText>
                        </Password>
                        <Group>administrators;users</Group>
                        <Name>administrator</Name>
                        <DisplayName>administrator</DisplayName>
                        <Description>Local Admin</Description>
                    </LocalAccount>
                </LocalAccounts>
                <AdministratorPassword>
                    <Value>password</Value>
                    <PlainText>true</PlainText>
                </AdministratorPassword>
                <DomainAccounts>
                    <DomainAccountList wcm:action="add">
                        <DomainAccount wcm:action="add">
                            <Name>domain admins</Name>
                            <Group>administrators</Group>
                        </DomainAccount>
                        <Domain>domain.com</Domain>
                        <DomainAccount wcm:action="add">
                            <Group>administrators;users</Group>
                            <Name>domain admin account</Name>
                        </DomainAccount>
                    </DomainAccountList>
                </DomainAccounts>
            </UserAccounts>
            <AutoLogon>
                <Password>
                    <Value>PASSWORD</Value>
                    <PlainText>true</PlainText>
                </Password>
                <Domain></Domain>
                <Enabled>true</Enabled>
                <Username>administrator</Username>
                <LogonCount>1</LogonCount>
            </AutoLogon>
        </component>
    </settings>
    <settings pass="specialize">
        <component name="Microsoft-Windows-UnattendedJoin" processorArchitecture="x86" publicKeyToken="31bf3856ad364e35" language="neutral" versionScope="nonSxS" xmlns:wcm="http://schemas.microsoft.com/WMIConfig/2002/State" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
            <Identification>
                <Credentials>
                    <Domain>DOMAIN.com</Domain>
                    <Username>domain admin account</Username>
                    <Password>PASSWORD</Password>
                </Credentials>
                <JoinDomain>DOMAIN.com</JoinDomain>
                <MachineObjectOU>OU=computers,DC=domain,DC=com</MachineObjectOU>
                <JoinWorkgroup></JoinWorkgroup>
                <DebugJoin>false</DebugJoin>
                <MachinePassword />
                <UnsecureJoin>false</UnsecureJoin>
            </Identification>
        </component>
        <component name="Microsoft-Windows-Shell-Setup" processorArchitecture="x86" publicKeyToken="31bf3856ad364e35" language="neutral" versionScope="nonSxS" xmlns:wcm="http://schemas.microsoft.com/WMIConfig/2002/State" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
            <ComputerName></ComputerName>
            <ProductKey>XXXXX-XXXXX-XXXXX-XXXXX-XXXXX</ProductKey>
        </component>
    </settings>
    <settings pass="generalize">
        <component name="Microsoft-Windows-Security-Licensing-SLC" processorArchitecture="x86" publicKeyToken="31bf3856ad364e35" language="neutral" versionScope="nonSxS" xmlns:wcm="http://schemas.microsoft.com/WMIConfig/2002/State" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
            <SkipRearm>1</SkipRearm>
        </component>
    </settings>
    <settings pass="windowsPE">
        <component name="Microsoft-Windows-Setup" processorArchitecture="x86" publicKeyToken="31bf3856ad364e35" language="neutral" versionScope="nonSxS" xmlns:wcm="http://schemas.microsoft.com/WMIConfig/2002/State" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
            <DiskConfiguration>
                <Disk wcm:action="add">
                    <CreatePartitions>
                        <CreatePartition wcm:action="add">
                            <Order>1</Order>
                            <Type>Primary</Type>
                            <Extend>true</Extend>
                        </CreatePartition>
                    </CreatePartitions>
                    <DiskID>0</DiskID>
                    <WillWipeDisk>true</WillWipeDisk>
                    <ModifyPartitions>
                        <ModifyPartition wcm:action="add">
                            <Active>true</Active>
                            <Format>NTFS</Format>
                            <Order>1</Order>
                            <PartitionID>1</PartitionID>
                            <Letter>C</Letter>
                        </ModifyPartition>
                    </ModifyPartitions>
                </Disk>
                <WillShowUI>OnError</WillShowUI>
            </DiskConfiguration>
            <EnableNetwork>true</EnableNetwork>
            <UserData>
                <ProductKey>
                    <WillShowUI>OnError</WillShowUI>
                    <Key>XXXXX-XXXXX-XXXXX-XXXXX-XXXXX</Key>
                </ProductKey>
                <AcceptEula>true</AcceptEula>
                <Organization>Company name</Organization>
            </UserData>
            <ImageInstall>
                <OSImage>
                    <InstallTo>
                        <DiskID>0</DiskID>
                        <PartitionID>1</PartitionID>
                    </InstallTo>
                </OSImage>
            </ImageInstall>
        </component>
        <component name="Microsoft-Windows-International-Core-WinPE" processorArchitecture="x86" publicKeyToken="31bf3856ad364e35" language="neutral" versionScope="nonSxS" xmlns:wcm="http://schemas.microsoft.com/WMIConfig/2002/State" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
            <SetupUILanguage>
                <UILanguage>en-us</UILanguage>
            </SetupUILanguage>
            <InputLocale>en-us</InputLocale>
            <SystemLocale>en-us</SystemLocale>
            <UILanguage>en-us</UILanguage>
            <UserLocale>en-us</UserLocale>
        </component>
    </settings>
    <cpi:offlineImage cpi:source="wim://PC/image/install.wim#Windows Vista ENTERPRISE" xmlns:cpi="urn:schemas-microsoft-com:cpi" />
</unattend>

one little problem i struggled with was, that you have to use the "short" domain name instead of the full domain name in the answer file e.g: yourdomain instead of yourdomain.local

i managed to do an unattended domain join with this answer file...

<?xml version="1.0" encoding="utf-8"?>
<unattend xmlns="urn:schemas-microsoft-com:unattend">
    <servicing>
        <package action="configure">
            <assemblyIdentity name="Microsoft-Windows-Foundation-Package" version="6.0.6000.16386" processorArchitecture="x86" publicKeyToken="31bf3856ad364e35" language="" />
            <selection name="TelnetClient" state="true" />
        </package>
    </servicing>
    <settings pass="specialize">
        <component name="Microsoft-Windows-UnattendedJoin" processorArchitecture="x86" publicKeyToken="31bf3856ad364e35" language="neutral" versionScope="nonSxS" xmlns:wcm="http://schemas.microsoft.com/WMIConfig/2002/State" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
            <Identification>
                <Credentials>
                    <Domain>yourdomain</Domain>
                    <Username>domainuser</Username>
                    <Password>domainpass</Password>
                </Credentials>
                <JoinDomain>yourdomain</JoinDomain>
                <DebugJoin>false</DebugJoin>
                <UnsecureJoin>true</UnsecureJoin>
            </Identification>
        </component>
    </settings>
    <settings pass="oobeSystem">
        <component name="Microsoft-Windows-Shell-Setup" processorArchitecture="x86" publicKeyToken="31bf3856ad364e35" language="neutral" versionScope="nonSxS" xmlns:wcm="http://schemas.microsoft.com/WMIConfig/2002/State" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
            <OOBE>
                <HideEULAPage>true</HideEULAPage>
                <NetworkLocation>Work</NetworkLocation>
                <ProtectYourPC>1</ProtectYourPC>
                <SkipUserOOBE>true</SkipUserOOBE>
                <SkipMachineOOBE>true</SkipMachineOOBE>
            </OOBE>
            <UserAccounts>
                <AdministratorPassword>
                    <Value>xxxxxxxx</Value>
                    <PlainText>true</PlainText>
                </AdministratorPassword>
            </UserAccounts>
            <BluetoothTaskbarIconEnabled>true</BluetoothTaskbarIconEnabled>
            <ShowWindowsLive>false</ShowWindowsLive>
            <AutoLogon>
                <Password>
                    <Value>xxxxxxx</Value>
                    <PlainText>true</PlainText>
                </Password>
                <Domain></Domain>
                <Enabled>true</Enabled>
                <LogonCount>1</LogonCount>
                <Username>Administrator</Username>
            </AutoLogon>
            <FirstLogonCommands>
                <SynchronousCommand wcm:action="add">
                    <CommandLine>powercfg -change -standby-timeout-ac 0</CommandLine>
                    <Description>don't go to standby after 1 hour</Description>
                    <Order>1</Order>
                </SynchronousCommand>
            </FirstLogonCommands>
            <RegisteredOrganization>yourorg</RegisteredOrganization>
        </component>
    </settings>
    <settings pass="offlineServicing">
        <component name="Microsoft-Windows-PnpCustomizationsNonWinPE" processorArchitecture="x86" publicKeyToken="31bf3856ad364e35" language="neutral" versionScope="nonSxS" xmlns:wcm="http://schemas.microsoft.com/WMIConfig/2002/State" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
            <DriverPaths>
                <PathAndCredentials wcm:keyValue="c1574a1" wcm:action="add">
                    <Path>\\server\reminst\distribution\Out-of-Box Drivers</Path>
                    <Credentials>
                        <Domain>yourdomain</Domain>
                        <Password>yourpass</Password>
                        <Username>user</Username>
                    </Credentials>
                </PathAndCredentials>
            </DriverPaths>
        </component>
    </settings>
    <cpi:offlineImage cpi:source="wim://server/microsoft/windows%20vista/wims/install.wim#Windows Vista ENTERPRISE" xmlns:cpi="urn:schemas-microsoft-com:cpi" />
</unattend>