A lot of that has to do with the car. Xray and Kyosho seem to be winning everything these days. The top Xray drivers here in the states are sponsored by RC America, so they run Maxpower (Nova based). Most of the Kyosho guys are sponsored by Sirio. That being said, I would agree that there are lots of good non-Nova .12's out there. I'm a big fan of the Piccos.
As for .21s, Nova just won the Worlds and the ROAR Nats.