"Since the time we implemented our DMCA () notification process, we've sent hundreds of thousands of warnings to customers but have only had to terminate the accounts of a tiny fraction of them," says Cox's David Deliman.

Less than one-tenth of 1 percent of cases have resulted in account termination, Deliman says. What's not clear is what determines whether an account will be terminated, and whether that judgment comes from Cox or from the RIAA. My request for that information was not answered prior to our publishing deadline.

AT&T

AT&T is participating in a trial program related to illegal file sharing and the RIAA, a spokesperson confirms. It does not, he says, involve "takedown notices" or a "three strikes and you're out" type of system.

"This trial is about customer education and deterrence," AT&T's Mike Balmoris explains. "We do not assume or make any accusations of wrongdoing by the customer."