50 freaking millions is enough to develop a AAA title, not a couple of expansions. I think MS got owned and ended up paying for most of GTA4 development costs, including the PS3 code base, rofl ;)
Also I seriously doubt they already started any work on the 2 episodes. Instead of working on the episodes they delayed the 360 version for 6 months so they could bring the PS3 version to the same level of quality to have a simultaneous release.
Also, there is nothing that prevents Sony from sponsoring the development of new DLC for the PS3 and also nothing prevents R* from making extra DLC content for both systems.
If the game sells well we will eventually see DLC content for PS3. Also, GTA4 is loved in Europe and we all know that either europeans love the PS3 or they just hate to mail RRoDed 360's across the Atlantic ocean for repair (it's not as easy as in NA, it's a pain in the ass).







