I'd call That Announcer "T.A." regardless of his real name. I wouldn't let people call me Mrs. Pepper in a real conversaion because that would irk me to no end, since I'm not a Mrs. (mind you, Pepper is rather cool).
Yep, we'd definately converse very well, but as for names, it kind of depends. For someone like TogetherAgain I'd use her real name, as Together Again is a song. But you, Bear, I might end up calling you Bear, because it sounds like a name. Same as Vibs, Ziffel, Beau, etc. Weird nicknames, but still names.
Very cool post, by the way. That's food for thought!