Not utilized correctly by Wenger. Don't think he is the player people made him out to be at Madrid and with his Germany performances, but he is certainly still very good.
He's a typical lightweight no10 where he needs other players to do his running for him and is sublime in between the lines if he has the space to do it. The problem is that in this league you need to be fit because you are constantly running and you don't get that much space which is why Ozil is struggling to adapt.
The obvious comparison is between him and Eriksen although I'd say that Eriksen is now working harder than ever before and he's tracking back and he has a better end product than Ozil.