I went to Pacific Media Expo yesterday, and there were at least three BlazBlue cosplayers. Not a huge amount by any means, but they were there.
Noel (she said that her guns were being used in the masquerade at that moment when I asked her for a picture. I never saw her again, so that's why there's no Bolverk)
Hazama
Taokaka
There were a couple of Guilty Gear ones as well.
Bridget (an actual trap, no less)
Baiken