Quite a lot of people don't like him, judging from the freaks who post on Sherdog.
Personally I think he is fantastic. He is a true fan, but also knowledgeable. He may not be right on every call, but his explaination of the ground game is fantastic. How many fights do you see him say "Now what you're going to see is X try to push the leg of Y away so that he can get from half guard to full guard" and then that happens? He really helps people to understand what is going on.
I like his attitude as well. He starts off with a lot of enthusiasm for both fighters, but if things are not going well he will call it like he sees it, and say, basically, "this is not good"- like he did with the Heath Herring fight.