Just because Blizzard fixed something they obviously overlooked and he used it before they fixed it doesn't mean he should be banned...
With that logic everyone playing SPriest right now is exploiting because we know Blizzard is going to fix them, and therefore all players should be banned and have their levels reset because they are using a "broken" mechanic to their advantage.
There's nothing wrong with people finding loopholes and using them to their advantage...he did the research to find it and clearly not many other people stumbled across the same thing so he deserves the credit.
Besides it's not like hes got his face in the camera screaming WORLD FIRST BITCHES.