I got the invite for buying Bulletstorm, and for the last couple of nights I've been playing the online multiplayer.
First and foremost: I have played the first two games, but I am not what anyone could reasonably call an expert. I played them both once, to the finish, because I'm the type that likes to get the story. I never played earlier versions of GoW multiplayer at all, so I can't compare it to that.
Now, on to what I thought...
I played about 12 Team Deathmatch games, and about 8 or 9 King of the Hill Games. I did manage to unlock Anya as a playable skin for multiplayer, as well as freeing up some weapons, but since I'm not a great player, I have not seen anything yet that wasn't already in the first two games. I got to level 5, and I did have a lot of fun playing, but for my experience King of the Hill was a hell of a lot more fun than Team Deathmatch. The action seemed to come a lot faster, and kills were happening all around you so much, that at times I would start up my chainsaw, only to realize I was targeting one of my own team.
I did see that you could unlock a Cole Train skin, as several players better than me had done so. It looked pretty nice to be honest. He's out there in what looks like a football helmet and pads, and it definitely stands out when you see it versus the other skins. I have no idea how to unlock this, as I have yet to even activate it.
At any rate, I did have fun with this, and I'm not a typical multiplayer/kill everyone on the other team gamer. I usually play games that allow for me to work with other players (Left 4 Dead is prevalent in my library for this). I have no idea what this is meant to indicate about the actual single player experience for GoW3, but I'm likely to get it anyway, because I want to know what happens next, much like reading a book series, or watching a television series. I'm a sucker for a good story.