Selected answers from the Dumb SEO Questions Facebook & G+ community.
Michael Martinez: Images do not confer PageRank-like value because they do not contain hypertext links. The algorithms are designed for document-type files that contain the links.
George G.: Lets say they do E.g see the image here and here is the anchor to the image
Michael Martinez: Googlers have always said that image links do not pass value. Do with that as you will. Run an experiment and see if you can determine a change in something.
George G.: I see. Any other way to benefit from it?
Michael Martinez: George G. Well, infographics became a great way to link spam one`s way into a penalty. I suppose if you can find a way to get people to link to an infographic post rather than republish the infographic with a link you might get some benefit. I really stopped caring about image links years ago because most of them were hotlinks from Web forums. I tend to block those when they become annoying (has no effect on what the search engine sees).
Dal Tavernor: I came across an ecom store doing a lot of this recently. It was like a huge image link farm. But they also include a hyperlink with the anchor as a ‘.’ Under the image. Very strange, not seen it anywhere else.