Perhaps just a regional difference. In North America I would say 90% of the Elite Men/Women are on carbon wheels, and even half of the beginners. Most people glue up their road race wheels for cross in the fall, and lots of the 35+ crowd have the money for whatever they want to ride.

Carbon or not, the road inserts make changing pads quick (less than 60 seconds per wheel) which is the real advantage. No need to readjust everything since the pad holder maintains its position.

No idea on the actual weight, but I saw on the VeloOrange blog that they are looking at selling a version of the 'RaboBank' brakes: