I don't talk too much about fannish things but this time...I can't help it. I should say there's spoilers ahead if you hadn't seen the season finale of Supernatural. There are a only a few things I'm going to comment on because I've only seen it the one time so far and there may be some things I get wrong. Feel free to correct me, if you are inclined.
First of all, the biggie - Chuck.
I don't think he was God. At least, not always. Until the finale, Chuck was a very unconfident person. He hated what he saw in his visions. He hated - and had plenty of troubles with - the process of writing it all down. He drank to forget, more often than not. Let's not forget how he was at the convention at the haunted hotel.
The Chuck we saw in the finale was none of this. He didn't even seem to be merely recording what he was seeing and there were no blinding headaches (if I remember correctly, this was a problem when we first met him last season.) He had no problem whatsoever writing the story. Rather, he seemed to be enjoying telling the story of the Impala and how it was intertwined with the Winchester brothers - and he was very confident in telling it. There was that one spot in the story where he even commented on how he liked how a certain line sounded.
The story itself was different in tone to previous ones. There was no pulp here. Just a story, lovingly told.
This Chuck was also drinking but he only sipped his alcohol - and did it quite properly, at that. There only seemed to be two fingers' worth in that glass. (On a side note, when Dean calls Chuck for information, was the call girl in the magazine named "Mary Magdalene"?)
So - was Chuck God? Like I said, I don't think he always was. Chuck was the Prophet and he did his job, however hard it was and miserable it made him. I think God stepped at the end. It was an act of compassion (mercy, even?) and reward for a thankless job well done. It also afforded God a way to intercede, using the Impala to spark Sam's memories of happier times and the love between the him and Dean. Besides, what was it He said? Endings were tough to get down.
On a side note: I don't think God was as heartless as it seemed when we found out He wouldn't be helping defeat Lucifer. We've known a long while that the last battle was supposed to be between Michael and Lucifer, both being angels created by God. We never expect a parent to choose between two of their children - so why is God expected to choose one of His over the other, even if one of those children has rebelled? So it's no wonder He didn't want to take sides.
I wasn't surprised that Castiel got his Grace back. In fact, after last week's episode, I would have been surprised if he didn't. He may have fallen and eventually lost his mojo but he kept his faith. It wasn't his faith in God, but rather it was a faith that he, Sam, Dean and later, Bobby would somehow get through this.
I call it faith because that is what it is. Way back in the episode where Uriel wanted to wipe that town off the map, Castiel tells Dean his orders were to do whatever Dean ordered. He may have started out only following and protecting Dean but somewhere along the line, Dean did as Dean does and took him under his wing. Castiel became family. Faith in God is good and all but when it comes down to brass tacks, is there anything stronger on this earth than family bonds? After all, who else will stand by you or give you a good, hard and swift kick in the assbutt when you need it?
I think this is exactly what Cas took back with him when he went back to heaven. He says he's not sure if God will ever show up again but he figures with Michael gone, the place may be in chaos. He's gone home to sort out his "other" family, maybe even using what he's learned from his time with the Winchesters.
So, has the contract between Bobby and Crowley been fulfilled? We never heard the details of the deal, did we? Crowley only said he would "borrow" Bobby's soul for a little while (and it seems to me that he knew a lot more than he let on in the previous episode, didn't it? Especially since he said to Dean, "How about we go for pizza when this is all over?" as they searched fruitlessly for Death.)
Anyway...I think the contract has been fulfilled. In past deals, the one making the deal always got a set number of years before they died and went to hell. As vague as Crowley's deal was, Bobby did die if only for a little while before Castiel brought him back.
I'm not sure what to make of Sam at the end. Was he a ghost, watching over Dean as he had dinner with Lisa and Ben? It would certainly be one possibility, since ghosts are able to mess with electrical systems. He wouldn't be needed in Hell since Lucifer had been re-caged and it wouldn't be impossible for him to get out, especially with a little help, like say from oh, God?
I don't know. It's going to kill me waiting to find out. :-)