I have the impression that panels are less popular than they used to be. When I was a kid they were just about the only way to get state-of-the-art sound. The Quads, then the KLH-9's, then Maggies and Infinities were light years ahead of the dynamics of the day and they're still competitive. But dynamics have gotten radically better over the years, while progress in panels has been incremental. Panels still seem to offer the best bang for the buck and IMO offer a more realistic presentation of acoustical music than even the best dynamics, but they're big, need lots of space, and don't play as loud as big dynamics.
It also seems to me that there's a bit of a hole at the planar high end, I think there's room for a line source tapped delay electrostat (which someone is working on) and for an all-out assault on ribbon technology. I'd really like to see a triple ribbon -- 2" magnet assembly with a thin mid tweeter flanked by two 1" midrange ribbons. I mentioned that to Wendell and he said they'd tossed the idea around decades ago, but that it was too expensive -- that last being what he ends his sentences with whenever I mention an idea.
