Bring on the spoilers

I finally got to watch The Avengers. I liked it, but I wasn't blown away. Maybe partly because I have never read any of the relevant comics.

So I invite those of you who had strong feelings about it to talk about what you loved/hated about it.

Also, where's the best fanfic? :)

(If I were writing Avengers fanfic, I would write it about Loki and one or more of his doubles.)