I think the actors have seven season contracts, and so far we know Jason Segel doesn't intend to renew after that. I don't see HIMYM going past season seven, they'll need to write some "big fat checks" to keep NPH and Jason Segel.... the rest of the cast isn't really doing much, but I'm sure they'd all like to focus on films.
I was waiting for this bump. The finale was only 1-2 scenes away from greatness, but they were a CRUCIAL couple scenes. As it is, some of the outrage is probably justified. I can't get too emotionally invested in a sitcom though, so I've been enjoying the backlash.
Season 9 as a whole was surprisingly entertaining, though. It will get drown out in talk of the finale, but S9 actually managed to breathe some life into a show that had slowly declined since about S4 or 5.