The last episode of Matt Smith's run saw the return of Gallifrey. The Timelords gave him a new set of regenerations in exchange for saving the universe on countless occasions, and The Doctor made sure to establish that his new goal would be locating his home world to bring it back, wherever or whenever it is.One of the major changes that was made when the show first returned in 2005 was that The Doctor was the last of the Timelords. He had trapped the Daleks and his own race in a never-ending loop following a brutal time war in order to keep them from destroying the universe. Bringing back Gallifrey and his former compatriots would give us a whole new set of possibilities and adventures. It would be a shame if Steven Moffat decided not to have The Doctor bring his homeland back to the universe, but he has ignored storylines before, so it's not impossible that The Doctor's journey ends without the return of Gallifrey.