ah HA! Barely visible arrows in the top right corner which act as a “like” or “+1.” They also appear to act as a bookmark of sorts.

However, I’m going to throw out an EPIC FAIL on this one by giving people the ability “hate” or “-1” in that it has the potential to discourage discourse (most likely by young and/or new members of the community) out of fear of being “hated.”

Just stick with the up arrow.

They’re what in other places is called “My marks”.
Look at the light gray arrows in the upper right of the post.

Liked +1