Peering agreements existed in the form they did because of the underlying assumption that traffic would be roughly symmetric. Services like Netflix that send
massive amounts of traffic in a single direction violate this assumption.
This is one of the underreported issues in the whole net neutrality debate. In the late '90s I worked in the WAN engineering group doing capacity planning at a big regional CLEC, which actually was a Tier 1 backbone provider. It was widely assumed in the industry that the flat rate pricing model -- pay $X for Y "guaranteed" bandwidth -- was living on borrowed time and would be replaced by actual usage-based pricing, paying for packets like you pay for gallons of water. The flat rate model only worked because we generally could keep available capacity well ahead of demand. We could do that because we were adding customers like crazy, and customers sucking down high bandwidth were outliers. If those prerequisites ever changed we'd be screwed.
Well, here we are in 2014 and ISPs like Comcast are not adding customers like crazy anymore, because most of the people who want high-speed data from them already have it. But the customers they do have are, on a per capita basis, using much more bandwidth now than they were five years ago. And this is only going to get worse. The nightmare scenario is basically upon us: capacity requirements are climbing faster than ever, but those requirements are no longer being driven by customer acquisition. Which means either the ISPs eat the cost of upgrading their infrastructure (ha!) -- or they raise rates.
But wait, doesn't Netflix pay for all their bandwidth already? Well, probably not: unless industry practices have changed drastically, even those backbone trunks are actually oversubscribed. If you pay for (say) a DS3 line, there's an implicit assumption that you are not going to be pumping 44.736 Mbit/s through it 24/7. Netflix breaks that assumption.
I don't know quite what the solution here is, and I certainly don't want the kind of dystopian "the ISP only gives you access to web sites that you pay for" future the sharpest critics paint. But I don't see this as a step toward that dystopian future. What I see it as is the ISPs trying to figure out how to work usage into pricing models without saying "screw it" and actually adopting a usage-based pricing model.