I founded Carnique somewhere early Saturday after having created Liandra at work on Friday (the release day, of course, doh). Or perhaps it was Friday, I don't even remember. Anyway, pretty soon after EU was opened, though not as soon as TLW.
Wow, i was relatively slow! i founded StarRock approx 10days after server opened, and even then thats cause noone else in the guild could be bothered.... (they kept on making long distance grps to chat, disbanding only when we needed grps to quest! LOL)
(StarRock originally comprised ONLY of my husbands work colleagues and me, now its still mostly connected by IRL somewhere, with a couple of in game additions - see if you can guess where he works )