Ok taking a look at the sales history of God of War, Gran Turismo and Uncharted 1 and considering the developers/franchise history heres my take.
God of War 3 650k first week, 1.8M LTD (On the rumoured 40M development budget will probably lose money). My reasoning is that its been a slow burn PS2 title and probably sold because its one of the few decent PS2 games still out on the market. Also its hardcore so it will see a low first week to LTD ratio, the fact that its so violent will limit its appeal. Also hack n slash games never really sell that well overall and the violence will prevent bundles. I also expect this game to be banned in Australia and Germany at least.
Uncharted 2 800k first week, 4.2M LTD. This is a game that a lot of people like, its a wider appeal game than God of War 3 and the online multiplayer looks inovative and well implemented so that should draw a wider base of people. Furthermore the developer Dirty Dog (Did I get that right LOL) has a history of being able to develop wide appeal games.
Gran Turismo 5. I would expect 300k first week Japan (Smaller userbase than PS2) and double the Prologue for first week sales and 750K for others and 350k Americas so about 1.4M first week sales. LTD sales I would expect to be 600k for Japan, 1.5M Americas and 5M others for a total of about 7M.
Tease.
