Nacurious lang ako. Ang dami parin kasing Windows XP fanboys around. Personally I dual-boot XP and Windows 7 but rarely use XP (I only need it because my ancient scanner doesn't have Vista drivers).
Though some benchmarks still point out that XP is still technically faster, and 7 is only about 10% faster than Vista on various benchmarks, I believe that Windows 7 feels a lot faster than either OS. Perhaps it's not a tangible and benchmark-able thing but I really don't see the point of going back to XP.
Of course if the hardware's old, no-brainer na yun to use XP.