Asking around paid off- what my bees were doing is either bearding or washboarding. I was directed to this blog first, and the blogger used the term bearding. I googled this, and found another blog site that talked about bearding. I noticed in the comments it had an update - that this was not bearding, but washboarding. The idea is that washboarding may be related to bees cleaning the hive. (!!!) More searching and a similar post, and found something about it on Beesource.
Because of the hives location, it's difficult for me to watch the front for very long without getting the bees a bit concerned about the big thing looming nearby. What I did see looked like all of these photos and videos. The photo isn't clear enough to see if their probosci are out. I did notice they were doing the same thing tonight when I got home, about 7:30pm.
Fantastic. :) Clean, happy bees!