I just started my Verizon service about a week ago and have noticed near-constant problems with Youtube as well. I can pretty consistenly realize 56/33 mbps on Verizon AND independent speed tests, though, and every other service runs like lightning.
I've tried several solutions to try and fix the problem of bad hops to Youtube and none of them have worked. From an online chat I just had with a Verizon tech (who was super nice and knowledgeable, btw):
[[Edit: Oops, I didn't know we couldn't post portions of the chat log. Basically, the tech told me straight up that the connection between Verizon and Google is at capacity, and we're at the mercy of the two companies working out a bigger back-end pipeline for Google services.]]
This was after we ran a tracert to 206.46.230.37 and the hops started timing out at the IP 206.46.228.129. I've tried blocking the following IP ranges in the router firewall: 173.194.55.0/255, 206.111.0.0/255, 173.194.7.0/255. These haven't worked for me though, and neither has switching to Google's Public DNS instead of having Verizon load me onto one automatically. Some people have had success with those methods, so I thought I'd give them a try.
Basically, it seems that the only thing that we can do as consumers is make a big stink about it to Verizon and Google in the hopes that they work out the bandwidth issues. :\