CinemaCon is currently happening in Las Vegas. Last night, Paramount Pictures and Marvel Studios debuted select footage from Thor for those lucky few in attendance. The scene they showed actually gives up one of the movie's biggest surprise cameos: The Avengers' Jeremy Renner as purple clad archer Hawkeye.
As it turns out, the character of Hawkeye will have more to do in Thor than just a quick end-of-credits walk on cameo. Jeremy Renner will star alongside S.H.I.E.L.D. Agent Coulson (Clark Gregg reprising his Iron Man role) in a scene that finds the bow and arrow expert showing off his expertise, as well as engaging in extended bits of dialogue. At this time, it is not know if his involvement in Thor will extend past this one scene.
There is no mention of Jeremy Renner's costume in Thor, or if he was wearing his infamous purple ensemble. The appearance of Hawkeye in Thor was meant to be kept a secret, but fans underwhelming response to the trailers thus far pushed Marvel's hand in revealing this character moment in hopes that it will encourage more people into the theater. Cry spoiler all you want, it was Marvel themselves who spoiled the surprise.