With the latest feature rollout, attaching pictures to comments on Facebook is now possible. Pictures are added by using the small camera symbol in the right-hand corner on the comment field. The feature was first brought available on desktop only, but support for mobile browsers was released later today. It is not yet available on the native mobile apps, but updates should be expected soon.
The rollout process seems to go on still, as not all statuses support yet the new feature. Page posts are completely free of picture attachments and not even all posts by friends have them. However, it is highly presumable that we'll see the feature coming up on brand pages soon as well.
If and when comment attachments should roll out to brand pages too, it will be both a challenge and an opportunity for community managers. No one will be surprised to see every other Internet troll make use of the feature. However, pictures also enrich the interaction between users and brands and thus give new ways to deepen the engagement.
P.S. GIFs are not yet supported. Too bad.