NBC.comHulu.
NBC.com isn't bad for streaming full episodes of shows, in fact it's much better than ABC.com. But both are behind Hulu in terms of functionality, ease-of-use and content. (Hulu not only has shows from NBC, but from Fox and its affiliated channels as well -- and it has movies.) I only see NBC.com as being useful if you want to use its direct download functionality to download shows rather than stream them.
Hulu seems poised to be the future of online streaming for full episodes of television shows. If I were an advertiser I would want that data.
When asked about the possibility of this data being released for NBC shows on Hulu as well, NBC's media contact, Joe Libonati, told me, "that would be a question for Hulu."
Apparently the two don't talk much.
[photo: NBC's show "Chuck"]