Great ending. It wasn't the best episode of the show, and nothing truly unexpected happened, but that worked in its favour. There were no unnecessary twists, no gimmicks, the finale was true to the characters and the story and ended in just the right way.
My favourite scene was Walt's confession that he did it all because it made him feel good. Most of the audience knew that all along, but it felt good to hear Walt finally admitting it to himself. It was interesting seeing Skyler's reaction to that, the relief she felt. I had never really thought about it before, but it must have been painful for her to hear Walt using her and the family as the excuse for his evil deeds all this time, as though she held some responsiblity for all the death and misery that Walt had caused.
I also liked that there was no flash forward to see if things had worked out for everyone. Did Flynn get the money? Did Skyler escape a prison sentence? Did Jesse get a clean start? Maybe. Walt thinks that they will, and he went to his grave thinking that, which is what matters most for the story. To confirm or deny any of that would cheapen the ending in my opinion.
I think many would agree that Breaking Bad is that rarest of things in television; a show where the final season is its best.