Check out the latest Iron Man promo image from the movie:

 Click on the image to see a larger version.

That pose is from a cover by Adi Granov from Iron Man vol. 3 #76 and has turned out to be quite iconic. Since appearing on that cover it was also used as the basis for an extremely popular comiquette and now as a promotional image for the film.

Here you can see the original along with the subsequent uses of the pose: