I literally noticed this about my MBA this morning. I had my top half assembly replaced because of a failed webcam. The top overhangs on the right and the bottom sticks out on the left. I called the store that serviced it and they can adjust that. I'm bringing it in Friday.
Sorry I was out of town. I did swing by friday and have my screen adjusted. Mine was just a left->right issue, and the store did it in about 10 minutes, 5 of which were probably the guy hanging out (I've worked retail). They do have adjustment screws, but as far as I can tell that would only help from left to right. I can't see if they could fix other issues.
Your best bet is to give them a call and see what they can do. I would call an actual store, and talk to someone there. I called the apple hotline first and they couldn't tell me if it could be fixed without replacing the entire top half again. The store i called simply talked to a tech about the issue, and got back to me within a minute or two.