David is right on.
But, I would like to have a safer, legal way to be able to look at my contracts and say that I'm in the average range for Aetna by accepting 130% of Medicare E/M charges and 150% for procedural codes...or whatever it is. Obviously, that's supposedly collusion if we all get together and try to have our rates all the same (which is completely silly). But it's probably not going to happen.
We just have to negotiate the rate that will keep us with each insurance and if it isn't good enough, quit accepting them.