I live in Spain, so
I obviously don't have Verizon Fios, whatever that is. I have a 10 mbps connection which should be more than enough to stream 1080.
I can only stream 360p without having to wait ages. To watch a 480p or above I have to pause it and usually wait for 10 minutes or so for it to load. "show video info" shows that it loads for about a 10th of a second and then usually waits about 20 seconds (occasionally it will only wait 5 seconds or so) before loading another 10th of a second's worth. Some videos take half an hour or more to load.
Occasionally it will work more or less OK (although never perfectly), but as soon as I change to a different resolution it will stop working again. The adverts stream fine. Other video sites work perfectly.