Long ago in a land far, far, away....oh wait wrong story, but close, I wrote the tutorial here on MSFN for using Vista PE (PE 2.0) to image XP using WIMs. Well here is the updated document using Windows 7. While originally tailored to imaging Windows XP, the same process applies for imaging Vista and Windows 7.
As always if you have additions, changes, find errors, etc. let me know and I'll update as appropriate and give credit where due.
Creating WIM Images for System Deployment Using Windows 7 PE 3.0.pdf
Link to Vista PE post: http://www.msfn.org/...post__p__674778