Since the new season begins tomorrow night I thought it was time for a thread. I've been looking forward to this premiere more then most.
We left off last season with Castiel getting a major power up by absorbing a whole boatload of souls, referring to himself as the new God. The wall that Sam had inside his head was removed by Castiel causing all his memories from his time spent with Michael and Lucifer to return. Even with that, Sam hasn't gone catatonic, though he's obviously not out of the woods yet. Raphael is dead and Crowley is on the run. The last scene we see is Castiel basically telling Sam and Dean to bow before him. Which I think we all know they are not going to do.
Anyways, seems like this new season will be promising. One thing we know is that Death is making a return this season, possibly in the first episode. Another thing the producers have said the season will focus on is the redemption of Castiel.
The big question for me though is if this is going to be the last season or not. Now I think the best seasons of the show were the 4th and 5th, but I think the show still has a season or two left in it(not counting season 7).