It looks like a pretty big spoiler has been revealed for The Avengers with some updated casting news. This could be a big plot twist in the film so if you don't want to know what it is then don't read ahead.
We all knew that Cobie Smulders was cast in the film as S.H.I.E.L.D. agent Maria Hill. But IMDB has been updated to say that she is also playing another character in the movie... a character named Anelle, so she is playing two different roles, but who is this Anelle character? Well, she's the princess and heir to the Skrull Empire! So it looks as if the Skrulls have infiltrated S.H.I.E.L.D. and that would be the big twist, that Maria Hill is in fact a Skrull.
Now, the character Anelle is known for opposing her father's policies. So her infiltration of S.H.I.E.L.D. can go one of two ways... she is trying to prove her loyalty to the Skrull Empire or she will fight with The Avengers against her father.
I think it's safe to say at this point that The Skrulls are going to lay a big part in Joss Whedon's The Avengers. What do you all think about this?