I will say up front that I train at a another school in the same area as the one the original poster mentioned, and I have heard quite often people questioning this particular instructors black belt.
Okay, just to give you a little more of the story and why the original poster asked (and to all of you flaming him he did ask, he's trying to get more information) about recieving a Black Belt from Rickson. I want to say that living in the area I've heard things (not good things) about a specific school and instructor in this area that is a Rickson Gracie affiliate.
When I first moved to Sacramento I heard people questioning this school (the instructor was a brown belt at the time), but I went to that school to check it out first, then tried the Charles Gracie Affiliate in the area, and based on the free class at each I was going to go to the Charles Gracie school. There seemed to be nothing wrong, really, with the Rickson school, but the other school's instructor just seemed better for my Jiu-jitsu.
In the end I went to neither, I ended up training with a Cassio Werneck purple at Sac State until Cassio moved back to Sacramento, then went to train with him. Part of the problem is that the Rickson Gracie instructor recieved his black belt shortly after Cassio moved back permently and set up his school advertising as the only Black Belt in the Sacramento area. I'm not saying he doesn't deserve it, I really don't know I never rolled with him or seen him roll (he didn't roll on the day I trained with him).
I trained at that Rickson school once, got a good work out and learned something. I personally have not had a bad experience or would say anything bad about the school. I encourage everyone in the area to check them out if they're intrested in training Jiu-jitsu. Also, check out Mario over at Bruddas (The Charles Gracie School), and also check us out at Cassio Wernecks. Then make your decision.