According to the Japanese PC Watch the next GPU generation will use a huge amount of power. The 90nm NVIDIA G80 will consume 175W and the 80nm ATI R600 will use close to 200W.
Either way, this is simply too much. The current 100+W is borderline insane, and adding half again to it is just silly, speed is OK, but I think we have just passed the point of being ludicrous. When you are at more than twice the power of the CPU, it is time to hit yourself on the head with the same high velocity cluestick that AMD and Intel have already experienced.