In light of today's info about LJ possibly blipping out on us, I'm going to be busy trying to back up my journal. I haven't done it for 7 months! (bad girl) Anyway, if things go blip! I'm at InsaneJournal under the same username.
I wouldn't get too worried yet. I would back-up, but I wouldn't waste good worry until the unthinkable happens. Like the Bat, be prepared! ;)
Fandom will find a new place if we need to. Pre-LJ, there was YahooGroups, and regular websites. Will fandom fragment? Not unless we all scatter to the winds. We will find a place.
For now, I consider Livejournal my home until otherwise! :)
liz_marcs has good back-up info.
Also, if you ever need to find me, email@example.com is my e-mail addy.
Take deep breaths, calm down, and make sure all your fic is on your hard drive and in some other back-up mode! :)