Netflix requires about ~5 Mbps for an HD stream. average download speed in the US is like 24 Mbps. Once again, they will not be throttling netflix
To give you a concrete, current example: YouTube is consistently slower over my TWC connection than through other providers. While it's not simple throttling, it's a known issue with Time Warner caching YouTube content to reduce network load, the point is the same: providers can favor or punish sites and there's little consumers can do about it. And YouTube doesn't require 5Mbps.