Speaking of still images, Jeff of Pixel Rally has posted more images from the Chicago set from when a lot of those stills were filmed. He also put together a comparison shots from the trailers & TV spots with what his camera captured last year. One of his observations is the building that gets squashed by the 100% CGI glass building (it was "built" on the neighboring empty lot) was changed between trailers, "they've made it look like there's a patio table instead of a person, and changed the styling of the building itself." He also has an image of Shia attacking a blue head while in Chicago which thanks to the TV spots we now know is Starscream so Jeff did a little Photoshop to the image to make the case. The comparison images are below, the full larger sized gallery can be found here.
Update Two need comparison images added by Jeff. One shows the "Power Glove" which actually appears to be a safety contraption as he swings around so can be "caught" by Bumblebee. The other gives you an idea of how cardboard face can be come more with Michael Bay and ILM doing their magic.
Update 2: Jeff, who was on site at the time it was filmed, argues that the glove is not a safety device, but "I think it shoots some grappling hook that Sam uses to climb up on the Decepticon, rides on it's head as he attacks it, and falls off, at which point Bumblebee catches him. There's other shots where the Josh Duhamel stunt double is trying to cut Sam free from the cable, and maybe he succeeds, so that's when they fall and Bumblebee skids in, Transforms, runs up the wall and saves them." He then provided a college to show the sequence of events (last pic below).