Ma Bell has a history of filtering your content (that's why the EFF is suing them over privacy violations re: NSA wiretapping.) Net Neutrality is NOT a concept that either RBOC is concerned with, especially now that they need content to fill those triple-play plans (FiOS + U-Verse). To get that content (or at least to maybe get reasonable discounts) AT&T has sided with NBC Universal. NBCU thinks that ISPs' should stop illegal downloads. Apparently, all execs live in a fantasy land.>
Two: the latency and CAPEX of such filtering would be huge. Think about it in terms of spam. Most spam boxes (like Barracuda) can only handle a max of 65k messages per hour for filtering. Can you image if you had to deep packet inspection on every packet running across your network? Big boxes would be required and administration would be a job in itself (like spam filtering is).
It's great in the ivory tower to say stupid stuff to get print and spin the comments to make you look good to the sheeple who buy your stock, but does reality set in? When they say Talking Heads -- that's about all they are.
For more on the MPAA, NBCU and ATT, read ARS.