No it's not the RTM, I suspect we'll see at least 1 more build as this version added some things that weren't in there before and might need further testing & fixing. Considering this will be the last SP that XP ever gets, it's a good thing they're making sure it's perfect, but I'm just an anxious as you are (this SP is 1.5yrs late according to MS's original plans). we'll most likely see the XP SP3 RTM release later this April. probably the 3rd or 4th week of April. I was wondering the same thing, i thought it was a service pack, not a rollup package what MS said there is wrong. ALL service packs for WinXP ARE cumulative. thanks for the link to build 5508, jhmac77. 5508 has to be rtm or a ealier buil;d like 5503,i can't see it hit build 5509 its vistas earlier build