In July, Facebook rolled out a new "seen by" feature for groups, which let people know who has seen a post or announcement in that group, and when. And, although Facebook didn't make much of a song and dance about it at the time, it looks like it is actually offering this feature on photos, too. As you can see in the screenshot below, the "seen by" feature in photos works just like the "seen by" feature for other group posts: someone who posts a photo to a group can see how many people in that group have viewed it, who those people are, and what time it was that they viewed the photo. And that information is not exclusive just to the poster, either -- others in the group can see who viewed a particular picture, too. Source: http://feedproxy.google.com/~r/Techcrunch/~3/5_3IwTGfHl8/
