I am probably wrong on this (I usually am) but he seems to be playing slightly differently since his return from injury. It might be him just easing himself back in but he seems to me like he is playing more regimented, holding his position better.
They say CB's hit their real prime between 28-32 and I think we are starting to see that with Kompany, maybe I am doing him a disservice, or its just the harsh reality of how disorganised we were without him, but to me he definitely looks like he has matured even more as a player. He has always had a slight element of rashness about him, but he seems like he knows his limitations now from any injury/fitness point of view. To come straight back in and perform to the level he has is testament to him, not many could do that.
Otamendi looks a completely different player alongside him too. Not often I agree with J. Redknapp but he is correct when he says if Kompany and Aguero were fit for the entire season, we'd be 10 points clear.