CBR has a first look at new posters promoting Marvel's big team up (click the images to enlarge) …
Directed by Joss Whedon, "The Avengers" finds the S.H.I.E.L.D. director assembling a team to pull Earth back from the brink of disaster as an unexpected enemy emerges to threaten the planet. Opening May 4, 2012, "The Avengers" also stars Tom Hiddleston as Loki, Clark Gregg as S.H.I.E.L.D. Agent Phil Coulson, Cobie Smulders as S.H.I.E.L.D. Agent Maria Hill and Stellan Skarsgård as Dr. Selvig.
[Source: Comic Book Resources]