To those of you desperately defending XP - why did you upgrade from Windows 2000?
I only upgraded to get media centre (MCE 2005 edition, four years after XP was released!) and still use the classic W2k interface. Also I still use W2k on my older PCs and servers.
For most people there has to be at least one 'must have' feature. It's no use having a number of 'nice' features it has to be a killer. For me even though I dual boot the only time I use Vista is for editing HD video where I need to use all 4gb of memory. I understand why the technology is supposed to produce a better OS but for Vista the whole is less that the sum of its parts.
but one thing for sure.... there is NO excuse to rule out Win7, it is everything that Vista should had been, it runs better on slower than machines than Vista ever will...probably even better than XP!