Drive-by Spoilers and Spec post
Zombie!Grandpa's Deal:
I think in exchange for hunting Alphas for Crowley and leaving Heaven Grandpa asked for a reset button wrt Mary and John. I think he asked that Mary got her wish and she and John raise the boys normal. No ceiling death, no Azazel, no nothing. Just Mary, John, Sam and Dean. A normal life. Sam a lawyer. Dean a engineer. John and her running the auto shop.
It's the only thing that makes sense, the only thing I can think of that would make a man like Samuel Campbell, who had spent his entire life fighting demons and who's family probably goes back to Biblical times doing the same, make a deal with a DEMON.
And if I'm right it's the perfect set-up for season seven because wow, what a monkey's paw that would be, especially if Samuel didn't word it right, and it's Crowley, you know he's put some loophole in there.
I mean if you were a demon, and you knew, without a doubt how shit needed to go down to make sure you ended up king of the hill, or hell as it were, what better way then to a: control the place where all the creepy crawlies go and b: to know the fate of the one family on earth who could jack your plans up good and proper.
If I'm right it would be very Doctor Who, The Year That Wasn't, with Crowley and possibly Castiel, being the only ones who know how things were supposed to be.
Not to mention that Sam and Dean would be totally unprepared for Lucifer and Michael because in the end they're STILL the vessels for both of them and that shit will play out no matter what AU happens.
Just my spec but my guesses have been pretty good so far so we'll see.
What do you guys think?