Monaco has been out for nearly a week on PC, and I'm loving it. As one of the most fun four player co-op games in a while, it's just as enjoyable to play while you're screwing up a mission as it is when you're succeeding.
Sadly, Xbox Live fans will have to wait a bit before they can get in on the action, as the game has been further delayed past the initial launch issues. Pocketwatch Games' Andy Schatz stated that it was a "minor but important bug" that causes online play disconnects.
He submitted a fix, but it wasn't enough, and he's working on another one now -- the dates are out of his control due to Microsoft's patch approval process. Andy also stated that a Mac version is in the works for a potential three to four week target, but nothing is set in stone.