The v1.3 update for GTA IV PS3 has been released to support the trophy system, similar to the XBOX 360 achievement system. When you load a save created with a previous version, you will be informed that the trophies are not retroactive, in other words, you have to start a new game to earn trophies.
The full list of trophies/achievements can be viewed on the achievement section of Rockstar’s site.