Lol, it's my icon xD
Anyways, it's kind of a SPOILER, so if you don't want to know [or any other people] so DON'T READ!
No, Thirteen's leaving is temporary, she will be back - And so does Taub.
According to Michael Ausiello, "The revolving door at Princeton-Plainsboro will spin yet again next month when Thirteen and Taub request their old jobs back."
So she will be back :)
