I think the meccas of BJJ in the US are definitely California, Florida, and probably New York. The problems I see with BJJ schools are that they are cyclical and pretty much based on if the school has a group of dedicated instructors or not. A lot of schools has instructors who go off and open their own schools and when they take students with them or the school is left with a less dedicated instructor, attendance starts to drop off. The school I've trained at is like that because its a bit in the sticks outside the main city I live in (which already reduces the number of new students we could have) and one of our main instructors went AWOL and hasn't been in for months. So the number of dedicated people are down a lot and there are barely any good people to train with on a consistent basis. We are arguably one of the top amateur MMA schools in Florida too based on records (outside of the big ones like ATT, Master's MMA).
I'm up in Jacksonville, Florida and the number of schools is exploding out here now for a smallerish city/town. BTT just opened up maybe a year ago and Marcello Bergo just competed in Eddie Bravo's Invitational. He's bar none the best instructor up here if you look at their record/background. The highest belt we have in town is 7th degree Coral belt Luis Palhares. Past that, there's my school which like I said is a bit away (35 mins) from Jacksonville in Orange Park, FL, but at one time was the best and most complete MMA school in the area. The most complete MMA school we have in town now is Ludus MMA which is near the beaches and has a lot of amateur and a couple pro fighters all with good records. Past Ludus and First Coast Full Contact (school I train at) you won't find a lot of MMA competition based schools in the area, but there are a lot of BJJ based schools like Gracie Barra, Machado, BTT (offers muay thai and BJJ, but not so much MMA), Palhares, a Muay Thai school, and a newly opened 10th Planet school.
In Daytona you have Pete White Boxing which has A LOT of good pros and amateurs and offers both striking and ground. Alex Nicholson just competed in the UFC actually (guy who got his jaw crushed by the Russian after proposing to his gf at weigh ins who is a pro now too).
Orlando has a Gracie Barra and ATT.
And the biggest area to train in is of course Fort Lauderdale/Miami area which has the main ATT complex in Coconut Creek which is expensive from what I hear, Master's MMA down in Miami, a Valante Bros, Popovitch up in Fort Lauderdale, and a bunch of other schools in the area.
