Well lets see. Obviously, his Jumping B move is insane, being that you can't touch him when he's falling, cept via Counter, for the most part. His Down Smash has fantastic speed and good kill ratio. His Forward Smash is incredibly powerful and his good range. His Down Air move pretty much stops everything coming up at him, just like his down jump. His Up Smash seems to have decent speed & power too. He's one of the best in Sudden Death, being that the Waddle Dee's kill instantly (I'd use those more too in reg. matches). The suck stops most dashes & thrown items too, and spitting out can kill someone. Even his Dash seems decent. His regular A combo move is fast and very hard to roll behind, not to mention that just like Snake, his regular A combo can someone hit from behind. His floating & Jumping B make it pretty much impossible to down spike him at all.
From what I can see, his only weakness is that his Final Smash isn't that good, and you keep killing yourself.