We presume the black and white dots on his arms and legs are references for the computer-generated visual effects that will enhance the suit in post-production. More after the jump.
The site also posted an image, below, from the set, which was posted by director Jon Favreau. We're guessing that Iron Man finds himself the hole in the donut. :)
Iron Man 2 is slated for release May 7, 2010.