The new feature is similar to the old “theater view” in that it takes the user into a pop-up carousel of photos. What’s new is that Facebook has moved the comments to the right side of the photo and added advertising below the comments field. In order to like or tag a person in the photo, you must hover over the photo and wait for an action bar to appear.
“If I were Facebook I’d still make the lightbox view much larger (like Google+),” Hawk wrote on his website. “When it comes to a photo in lightbox view, bigger is definitely better.”
As Hawk notes, some believe this viewer is very similar to Google+’s lightbox. The comments on Google+ also exist on the right side, and the background greys out similar to the Facebook lightbox.
We have reached out to Facebook to see if this rollout has been completed. We will update upon hearing back.