Yes, I do know that many CMA now have belt ranks, at least since they came to the US. But the schools I have been associated with do and did not. Could be where my Sifus came from and/or who their teachers are/were or the styles they teach. I have said before here on MT that I am a traditionalist and it is likely I get that from my teachers in CMA. Also, for all intensive purposes, I train Northern styles and those are also Internal CMA styles, except for non-sport Sanda and my sifu does come from the North but still has no ranking system.
However I will say I have been to seminars at YMAA and they have a ranking system but I do not think it is belts.
One thing I have noticed is that internal styles do not use a ranking system. I wonder if it's a philisophical thing between internal and external practitioners and teachers?
One example of the white, brown, black system I think was in China. It was a wushu school in Xi An province. The school kept the groups seperated but only the BBs wore their belts. When we had the Qi Gong seminar, the master who taught it was in street clothes with about 50 keys on a loop attached to his belt. He made a lot of noise.