I just browsed through several of the previous WOTTs, and they're all locked, even back to ones well before Wendy was here.  So yes, I think that locking the old one on Friday was normal procedure.

As far as who starts a new one, there isn't any sort of assignment, but normally the people who frequent the WOTT usually start it.  When I start browsing the forum on Friday mornings, the new one is almost always already there.