I think I'll always like Dean best, but I agree with you about the way he's been this season. It would be pretty inhuman, though, if all the crap he'd been through hadn't started to take a serious toll on him. I just wish he wouldn't be such a meanie to Sam because of it :(

Which is why that end scene was so excellent, you're right. Sometimes their heart-to-hearts can get a little repetitive, but this one made me really happy because they were actually breaking new ground in their relationship. All Dean needs to do now is let Sam drive a little more.