I just saw this interview in Gametrailers with Jack Tretton from Sony...
At the end of the interview(5:55), Keighley asked about Agent, and then questioned if it was still exclusive for PS3.
Then I became surprised, because Tretton(who usually have very confidence about all things regarding PS3) stuttered a little, and responded that it's up to Rockstar guys, and that PS3 will have a great Agent offer.
So, there is a great probability that the Agent's exclusivity is not certain. What it WILL happen, is that AT LEAST the Agent will have exclusivity content for PS3







