Verizon FIOS was doing this about a year ago in the NYC area. I was getting crappy YouTube and Netflix playback but everything else was fast. My solution was to use a VPN service, and suddenly I was magically streaming Netflix and YouTube in crystal clear HD.
I think what was happening is that the VPN service had servers in the NYC area that had great connections to the local ISP network, and they also had a great connection to the Netflix servers, vs Verizon was deliberately keeping their pipe to the Netflix servers small so that there was limited Netflix bandwidth entering the local ISP network.
Setup the hurricane electric IPv6 tunnel broker and you should be immune to disputes between Verizon and Netflix or YouTube as long as the peering links between Hurricane Electric and Verizon remain congestion free. Both Netflix and YouTube traffic will run over IPv6 and HE is a tier one ISP known for aggressively peering with everyone. They would likely be the last ISP to try to charge Netflix and YouTube for connectivity.
I think what was happening is that the VPN service had servers in the NYC area that had great connections to the local ISP network, and they also had a great connection to the Netflix servers, vs Verizon was deliberately keeping their pipe to the Netflix servers small so that there was limited Netflix bandwidth entering the local ISP network.