Seems like this is really about training their consumers to define the quality of their internet by their reachability to the Netflix CDN nodes.. Smart move on Netflix's part.
I'm a software engineer with all sorts of shit hooked up to my 100mbps (thanks Comcast for no gigabit in your worldwide headquarters city of Philadelphia) downlink (still 10mbps up because you know...) and Netflix is absolutely my #1 concern at home.
Eh, netflix maxes out content at a fraction your comcast speed. Doesn't really matter if Netflix is going 50mbps or 100mpbs. Making netflix work is important, but I'd be pretty disappointed if my ISP was giving me 20mpbs, even though Netflix would never need that much.
And, having your pipe overloaded by things other than Netflix. I have two kids watching Youtube on pads and a wife watching TV in another room. With my fake Uverse (DSL) the TV uses the internet connection so, we are often streaming four different videos at the same time.