According to PSM the PS3 should be available worldwide in 9 months or so. Interestingly they had some information on GTA4. We quote:
“…specifically, [Rockstar] are going to be using the high data transfer bandwidth of the Cell CPU, RSX GPU, and Blu-ray Disc to use several streams of game info simultaneously.”
Rockstar North is said to have had its dev kit since August this year and is currently working on a brand new game engine for their next-gen GTA titles. Rockstar is aiming to create a photo-realistic city for GTA 4, complete with seriously advanced AI for the game's NPCs.
The game's city is still unknown, but we do know that it will be broken down into smaller, more detailed areas at the engine level, into which the game designers are going to be able to pour more textures, more object variety, and tons of details such as discarded soda cans with their own physics.
Expect screenshots and more detailed info on this title early next year.
Sources: Sponge and Computerandvideogames.com