If MS hadn't bought GTA DLC and Acquired FFXIII as Multi-platform game, then they would be far behind the PS3 in sales right now, so the deal with Rockstar and the fact that they acquired FFXIII to be on their system as well as the PS3 did work out well for them.
More people would have bought GTA IV for the PS3 and more PS3s too if they had known GTA IV dlc would eventually be coming to PS3 especially since the PS3 version was the highest rated version of the game.
And if the decision to make a multi-platform version of FFXIII wasn't released so late in the game's development cycle, then FFXIII would have been out for the PS3 worldwide possibly for Christmas 2008 with FF Versus XIII out as an exclusive Christmas 2009 so the PS3 would be well ahead of the 360 at this point in time and like the Wii over the 50 million sold mark and actually in a better striking position against the Wii if FFXIII had released worldwide Christmas 2008 as a PS3 exclusive.
Both situations MS acquiring GTA dlc and a version of FFXIII worked out well for them and also prevented PS3 from being within striking distance of Wii at this point in time.
