This raises two questions. First, why wan't this available at the same time as SP2? One could go deeper and ask why wasn't MBSA simply rolled into SP2, but I'll pass on that one. The second question is: where's the updated Application Compatibility Tool Kit?
XP SP2 is running reasonably well on my main workstation, but now that SP2 is out, I feel it time for a complete rebuild from the ground up, if only to get rid of all the little bits of random beta stuff still on this box!