I was pretty upset with Marshawn for not staying in bounds on two carries in a row. You take the risk of decapitation around here if you bring up something negative after a win, but since it did come up, I think the coaching staff obviously needs to address this issue with ML.
As for the side-stepping that some have mentioned, I see it more as Marshawn just looking for holes that aren't there. That East-West movement, IMO, is not a "tendency" problem for Marshawn. It's just that there are no holes for him to hit. O-line's fault, not ML.