PC
As a historically console first gamer, I find myself wanting a new rig more and more these days. Over the next few years the PC will have Dawn of War 2, Starcraft 2, and Spore. Sign me up please.
Now in terms of consoles, I would have to rate it 360>Wii>PS3. The 360 has plenty of games that I like, the first party games on Wii are good, and there has yet to be anything on the PS3 that justifies the price for me. That will undoubtedly change when the PS3 gets a price drop and more games hit this fall, but right now there are only a few titles that look compelling to me (Warhawk, Ratchet, Uncharted).