windows 7 installs everything you would get in ultimate no matter what version you run, it just has all the features disabled. this is one of the things i dont like about 7. perhaps its because im old skool and dont like seeing the os eat more drive space than it needs. i cant say im 100% happy with ms windows, and my many attempts to use linux have left something to be desired. so thats why i wait for
this to go beta. so that i can get the best of both worlds, without having to really give up any actual hardware/software compatibility. i can continue using firefox, photoshop 7, max 8, winamp, notepadd++ and pidgin and all my windows only games, but still be using a free and open os.
of course all this talk of operating systems. more cores is about bringing more resources to the pool, it really has nothing to do with how those resources are spent. buy a quad core because the os and your software will run better and you can do more things simultaneously without bogging down the system. buy one if you want a modern bloated os to feel like its not eating your system whole. its as simple as that. do not buy one if you feel you dont need it, like if you can trim your system to run on 486 without much trouble, or if youre upgrading (cpu upgrades are bs anyway, i only ever upgrade ram and video cards, anything else is a waste of money) and your system dont support it.
im planning to spend $400-$600 on a new computer this fall, and so far its gonna be no trouble at all to get a quad. its just getting so damn cheap to buy hardware, i really dont see any reason not to get a quad.