xbox by far.
Get on xbox better controls, party chat to mess with friends who also have the game

iirc the DLC cmes first on xbox too, PS3 also has some save file issue or something or other.
a year or 2 later get it on PC and download the mods and such by then the best mods will be out and the community patches will fix most the bugs
1. They have basically the EXACT same controls.
2. Just use Vent on PS3. Its 10x easier and more clear than XBOX's party chat.
3. The PS3 save file issues was fixed, and XBOX still has texture issues.
You can't go wrong either way.