They have that in DC already, although I'm not too sure what the fines are. Its tricky, cuz some people are fine without the headset and some are 1000% worse drivers.

I have a feeling it will eventually become a law everywhere and car manufacturers will eventually have Bluetooth (or whatever the technology at that point is) built into the cars and they will automagically connect to your phone so you have no option but to drive hands free.

More laws do suck, but there has to be a happy medium between citizens' comfort/freedom and everyone else's safety. Gun laws are another good example.