I've searched already and believe the answer is NO, but thought I'd verify here with real-world users...
Is there a way in Chatter to tag a "Group of users" (perhaps a Queue?) instead of or in addition to @User? I did notice (by simple testing) that there is a hash tagging system (I personally could care less about Chatter and don't use it as the Admin) via #tags, but no other tagging delimiters were discovered.
Thanks!