I've had a beta membership since it came out (I'd guess about six months), back when invites were limited.
Hulu does some things great. For the most part, I don't even mind their ad delivery (although if you're using FireFox and AdBlock Plus, you could figure out how to filter the ads out of their shows if you wished).
My biggest issue is that when they have a show, they often don't carry every season for the show --sometimes you get just the first season, and then you're stuck. Second biggest issue is that the ads aren't placed at the spots where commercial breaks would be: they just pop up randomly at points during the show, rudely interrupting it. It's only one ad for perhaps every 15 minutes of content, and a 30-second spot at that, but their timing really sucks, and they could fix this.
On the bright side, I got to watch all of the original Battlestar Galactica, and some of my favorite older shows. Currently I'm watching Total Recall: 2070 which I'd never seen before, and I'm finding it pretty good.
Intel Q9450 @3.2GHz, Gigabyte GA EP45-UD3P, 4 x 2GB G.Skill @4-4-4-12
Antec P160SW case (modded), Xigmatek 750w PSU
3x 500GB (RAID-5), , OptiArc 7200S, ASUS E818A3T
Creative X-Fi XtremeGamer, Hauppauge HVR-1800, Radeon 4890