I think Insanejournal is the best way to go. The owner is fandom friendly and it seems to run better than either of the others (so far). GJ have a dubious reputation for deleting people, although I have to admit I have not see the actual evidence for this and I don't think JF will take the numbers and the +18 rule knocks off a lot of my flist. I also hate the user interface - it's limited. GJ's user interface is plain broken in places.
So if I do jump, that's the way I'll go - to Insanejournal. If you want to add me, here is a link to do so. So much so that I have a permanent account there.
At the moment I have an open friending policy - you friend me, I friend you, unless you are under 16 (sorry, but the occasional locked post really isn't what I'd want young teenagers to see). My fic is, as ever, unlocked.