Well I got a 16 minute demo of his gameplay. Most of it is extremely boring, but he does track a few guys a few times. I think he knew I was there to spec him, so my bad really.

Also he seems to press his face against walls. Like, a lot. In normal gameplay, you practically never have your face so close to a wall that you can't see anything else that is going on. That's because it's easy to get killed, as you can't see anything (durr, your face is against a wall, how could you see anything?). This coupled with the prefiring and tracking, I'd say he's wallhacking.

I'd like to get another admins opinion on this though.