It's to do with the Hardware I have and the Software I use.
I don't like the 'hoops' that I would have to jump through to do certain things with Vista or 7. Also I don't like the idea of using 'wrappers' or things like 'alchemy' if I don't have to. Then all the software and games that won't even run at all under vista or 7...
Funny eh, Microsoft tell's man to upgrade from XP to 7. Man finds his old computer or software no longer works straight out of the box as it use to or not at all. Microsoft responds with "Oh, try the included WinXP Compatibilty mode we included". (Wow, our new OS is SO good we need to include a compatibility mode to run software you were running under XP!)
Good luck with that. If it works at all, it would be slower than original WinXP and also does not do video card 3D hardware accleration at the least.
It's like upgrading your shoes to a new flash pair and then breaking one of your feet. Your not going to move faster if at all.
Ofcourse you could always dualboot or throw 50% of your software away and 50% of your previous computing interests as well.