Well i recently reinstalled Vista, Ultimate 64-bit, i figured i would give it another try, i was having problems with media stuff on XP so i nuked my HD and installed Vista. I dont know how many of you have it, but, being it was a rely quick switch over, meaning like in a couple hours i had vista up and running to where i needed it. Now i noticed a lot of performance changes. Many of my programs ran quicker than before and certainly more efficiently, some didnt work at all, but i knew that, they didnt work on xp

but a DL manager i use, FlashGet, it not only DLed faster, not much but i noticed it, but it also didnt run, as a program, dog slow like it did on XP. I also unpack stuff with WinRar much faster, i do all those things that are all calculations and what not, much faster, like twice as fast.
Granted i have an awesome system, but somethings i think are for the better. Yeah I use more RAM and all, but... well vista actually recognizes all 4GB of my RAM, unlike XP which did less than 3GB, and a few processor heavy games run at much much less resource.
Over all, i like it.
oh, and btw, im gunna find out of MAC OSX Leopard will work

, doubtful, but i run nVidia and Intel, so maybe

hehehe ill keep you posted.