The main gist seems to be that they will run cooler (I wonder about that) and less apt to warp due to heat. Will an aluminum carrier be more prone to failure due to repeated braking stresses? It'd be a Bad Thing(tm) if your brakes ran without rubbing, but you could eventually count on them to explode on a big downhill.
Most mechanicals work by warping the rotors. Will they work with these new rotors?