If you look up "verizon throttling netflix" on Google, you see a bunch of 2nd-tier blogs and news sources all pointing at this article. I'm not sure I'd take the chatlog utterance of a Tier 1 tech support kid as gospel writ, particularly as half of their answers are some form of "yes sir, you're right sir, is there anything else sir so I can get started on this stack of 22 people piled up behind you." Time Warner, on the other hand, has been throtting Youtube for lo these many months. Or at the very least, throwing it onto their pokiest DNS. Net Neutrality didn't do shit about that. Verizon might very well be doing the same… or Netflix might just be sucking. The service is outright unusable on Roku due to Netflix itself deprecating the devices. Considering recent plays, I doubt things are as simple as they appear.
I use Netflix on Roku several times a week and don't have any issues with it. That said, it's probably because I don't realize how much better it looks/responds on other devices.
There's an iphone app that makes it better, but it works over the network. And when I say "network" I don't mean "your wifi" I mean "it connects to Roku's servers via your wifi so that every time you hit an arrow key it has to go to your hub, through your modem, up to Roku's servers, back down, through your modem, back to your hub, and to the Roku." Which means it's borderline useless at the best of times and completely fucked 90% of the time.