How is Far Cry 3?

It hasn't come out yet in NA (officially anyway) and I was really considering it, until I found out the "free roam" co-op was restricted to a very small portion of the island where the 5 or so cooperative missions are located. Is this true? That really kills it for me, I'd envision a game like this to be awesomely fun if me and a buddy or two could just roll around fucking shit up.