Mark Ruffalo just tweeted out the poster:
Despite what you may think, it’s not just a crop-and-zoom of the original group poster. The pose is the same, but the background is slightly different, mostly with some Ultron stooge-bots in the shadows. Sadly, it does not appear that we’ve got any hints hidden in the background, but it’s kind of impressive how thorough they were with the Hulk’s design. Zoom in on the large image, and you can see they’ve put in details like knuckle hair.
Hulk smashes — and we suppose we’ll see the rest of the team, too — on May 1.