I highly doubt that Walter will die, that kind of ruins the whole point of the story because he's the main character. Unless they switch the story to Jesse's life, which would be cool but wouldn't make sense because Walter is always the one who has to convince Jesse to start cooking again.
I'm sure Walter will come up with a good excuse, and the story will continue but it won't be the same because Hank will be suspicious and probably question or track Walter, eventually leading to the truth. But regardless of what happens I think it will be a great season, so far it hasn't failed to disappointing me in any way.
Amazing show.
