Just a random idea, but for me I definitely retain vocab that I ran across in anime/manga/Jpop/dramas way better than pre-fab vocab lists.
I would be an interesting feature if each episode came with an Anki deck for the varies levels of vocab that appear in the episode -- you could probably even make submission a perk and get the fans to do the work ;-)
Over time, you could even eventually build a WWWJDIC dictionary with short clip(s) in each entry showing the word used in context in some anime/drama situation. Could become a valuable asset for Crunchyroll.
Anyway, I'd use it. (I'm not personally associated with either of these projects, BTW)