If you haven't checked out Hulu yet, it seems you're quickly becoming a member of another technological minority group. Due to its ability to secure partnerships with several major media outlets (chief among them Fox and NBC/Universal), they have fast become THE destination for watching television broadcasts online.
April marked Hulu's first month of full operation outside of their invitation-only Beta testing and Nielsen Online's April video streaming statistics show Hulu is already #1 in viewership among "TV sites". Users watched 63.2 million videos and spent an average of 129.3 minutes per month. That seems like a tremendously high average, but bear in mind, Hulu is a very different site than YouTube, whose average video is 2-minutes of user generated content. These are full episodes of professionally produced content streamed at fairly decent video quality. In fact, I have several friends who have cut their ties with cable and satellite providers altogether because they can find most all of the shows they'd want to watch online.
The quality and user experience are pretty great and the ads are somewhat minimal (they drop a 15-second spot in wherever the TV broadcast had a regular commercial break). Unfortunately (but not at all surprisingly) they have recently announced plans to insert more ads and will assuredly make their platform just as littered with commercial interruptions as traditional TV.
My only real complaint is the sporadic nature of their programming lineup. Though a tremendous variety of current and classic shows (and even some feature length films) are available, it's pretty random as far as which episodes from which seasons are available to view at any given time. Just a guess, but I'd assume that it all has to do with contracts and agreements and DVD sales and syndication. Over time, those gaps will be filled in and I'm sure they'll offer the ability to purchase commercial-free episodes via their site or a partnership with an online retailer.