GTA IV sales are amazing and the game is going to show some of the strongest legs ever. First week 4.5-5M easy. Lifetime 9-10 million. I expect GTA IV to outsell COD4 this year and as PS2 owners start upgrading their consoles we can expect a huge boost for HD consoles. Nintendo were wise to unleash their 1-2 punch of Mario Kart and Wii Fit.
Take Two 's in house teams are developing the following games
Bioshock 2 (PC,PS3,360),
Civilization Revolution (PS3,360,NDS),
Midnight Club (PS3,360),
Max Payne 3 (PC,PS3,360),
Red Dead Revolver (PC,PS3,360),
Unannounced 2K Boston (possibly X-com) title (multiplatform),
Mafia 2 (PC,PS3,360),
Enemy In Sight (PC,PS3,360),
Don King Presents : Prizefighter (multiplatform),
NHL (PS2,PS3,360),
MLB (PS2,PS3,360),
College Hoops,
Top Spin 3 (multiplatform),
Prey 2 (PC,PS3,360),
L.A Noire (PS3, ???)
Apart from these Take 2 also publish games for various developers. Starbreeze, Bethesda, etc ..
Recently Sega has taken the mantle of developing crap movie2game franchises.
Take 2 is not a one trick donkey. Considering the 15 odd studios they own, the exclusive MLB license, 30 odd gaming franchises etc .. 2 Billion is a pittance.