I'm hoping since GTAIV runs so well on my PC that it will be able to handle this game.
I have an Intel Quad Core @2.2 Ghz, a ATI HD 5850 ( 1 GB DDR5) and 4 GBs DDR2 RAM running on Windows 7 Ultimate.
I have an i5 Processor, Same GFX Card, and 4 GB RAM with Windows 7. There are some slight hiccups, as the engine for the game was not optimized very well. I got about 40 FPS when there was either a lot happening on screen or there were a lot of zombies, and I got around 60 FPS when there wasn't much going on and there weren't too many zombies around. Loading is improved, but only by a few seconds. Most cutscenes don't even have to have a load screen like the console version, it just fades to black then the cutscene rolls about a 2 seconds after. But yeah, blame the framerate drops on the game engine, I run every other game I own maxed and i never dip below 45 FPS, most the time I'm at 60 or higher.