UberSchwarz: Alien vs. Predator
When that one was first announced, I admit I was expecting it to be utter crap, in no uncertain terms. However, seeing what I've seen since then, I think it's in with a very good chance indeed. The Predator certainly plays more like the film version than he did in the prequels, that much is for sure.
UberSchwarz: Half-Life 2: Episode 3 (If it ever comes out!)
Indeed. It's only going to be, what, four hours long? Using the same 5 year old engine... Come on Valve! Pull yer damn finger out already and get it done!
UberSchwarz: If I have my new desktop built by the time the 360 games release then I'll probably buy them for the PC instead if available.
All of them will be available on PC. Although it's fair to point out that the Halo games will only be compatible with Windows 12.