@Gargron First, thank you for building and admin-ing this instance. :D Came here fleeing Nazis and other scum. Glad to be here. I wish there would be a way to "globalize" usernames / identifiers. You can't do much about this directly I assume. It's the one advantage Twitter has at this point. :) Thanks again for running this show!
@GMRaphi Advantage or disadvantage is very subjective in this case. There's an infinite amount of available usernames, so if you're "dave" and someone else already snatched that, you can still get it somewhere else. Or host your own instance. In that way the usernames are like e-mail addresses.