If you haven't seen the HardOCP video footage of Ghostbusters running on a quad core PC with a GTX 280, it's definitely worth checking out.  Their engine scales "infinitely" based on the hardware and does all of the physics work through the CPU you're using which means that a high end quad core CPU or an I7 should kick ass in this game.  Comparing this to some of the PS3/360 footage I've seen, I gotta say I think the PC version is going to be the one to latch onto.

http://hardocp.com/news.html?news=MzkwMjUsLCxoZW50aHVzaWFzdCwsLDE=

The game is retailing for $30 on the PC, half the price of the PS3/360 versions, which also makes it a lot more attractive.  I may just end up grabbing this and the Wii version so I can enjoy the best of both art styles used in the game.