I am playing through Mercenaries 2 so I can complete a review for Blogcritics and in general I am enjoying the game. The graphics are both breathtaking and craptacular at times, but everything (and I mean everything) can be blowed up and that is awesome...sorry...Awesome (with a capital A).
But what is MUCH more impressive is the drop in/out co-op. Yes we have had that before...wait NO we haven't. While playing through my SINGLE player campaign I accepted a mission and 'bloop' someone joined my game, we completed the mission, both got paid...'bloop' he left the game. I was stunned, this was a true breakthrough in gaming, no extra setup, no invites (although you can do that), just people joining and helping.
I gotta say it was awesome...check Blogcritics in the near future for the full review!