Amusing anecdote (to me, at least). After about 2 months off of WoW, I decided to try it out again, mostly to see how the 4.1 patch is. Bear tanks fixed!? I feel my addiction coming back... So I launch, patch, and get ready to play.
Seems like if you're off for a certain period of time, Blizzard needs you to verify your Battle.net account. So I go to Battle.net, and am told to enter:
Account name/e-mail
First Name
Last Name (if applicable)
I know my account name/e-mail, but apparently I don't know my first nor last name, as I keep getting an error. I'll probably need to call Blizzard up and get them to correct it.
TL;DR: they always come back.