Ah...yeah, I didn't understand that at all. 
When I hover my mouse over a portrait, all instances for that unit highlight so it looked like some kind of weird duplicating picture bug.
Sorry for the false bug report, but it is definitely confusing and a break from standard convention from the global map as well as pretty much any other game in this genre that I've played. I'm not saying this is a bad thing...just that it is very different. Now that I understand what is being displayed, I can see how it is very useful in being able to plan out actions between various units over multiple turns.
