The user-interaction tag is one of our most common tags but it's not a term I've ever heard before this site. I'm thinking maybe people use it as a synonym of interaction-design but user interaction sounds more like a way of saying "human computer interaction," which on this site is a uselessly broad tag.
Should we nix or synonmize this tag? I'm learning towards nixing it as I bet a lot of people just type "user" into the tag bar and see user-interaction pop up and think "gee, that applies to me!"