I think many bike commuters are in it to save a buck, which doesn't fit with paying $2000 for a bicycle with the components of a $1200 aluminum model. Also, most CF bikes are racing frames and have little or no provision for racks etc. and a low weight rating.

I've got no qualms whatsoever with CF as an appropriate material. I really believe it will not be very long til there are carbon fiber bikes at Wal-Mart, as production quantities increase and moves to China or beyond.