seems to only let you in on pre existing characters, new chars get punted out x__x
No, it's just random.
You can log in and not see NA/EU servers, or not see JP, or not see any, or see all. The servers are getting slammed, that's all.
I created a character on a JP server to tailor my graphics settings to how they'd look in Ul'dah and loaded fine. My 1.0 character took around 11 tries though to actually get into the game.