[WARNING: While the following article is mostly speculation, it may include spoilers. Anyone who does not want their thoughts about Breaking Bad provoked should NOT read this article!]
Will Harris posted an interview with Bryan Cranston today for the Onion's A.V. Club. It covers a scope of topics ranging from Bryan Cranston's other upcoming work in Batman: Year One to questions about what it's like to direct an episode of Breaking Bad and Walt's trajectory through Season 4. I noticed an interesting comment that Cranston made when asked about the tension between Gus and Walt:
"He still has lung cancer. That hasn’t gone away. 'Remission' only means that it hasn’t progressed exponentially. By the end of two TV years, he will die of lung cancer, if not of something else first, and by the end of this season, we will have accumulated about one full TV year from that diagnosis."
That quote says two things to me.
First, not only will the events of this season take place over the course of a year (almost as long as the entire series timeline to date) but that Walt will once again have to deal with the issue that started this whole series off in the first place, his cancer, in a more direct way. I've been expecting this to a degree since cancer doesn't just "disappear", even with treatment. That ticking clock is still there and it will be nice to see Walt pressured by it once again. And imagine the places Walt will go over the next "TV year"!
The second thing this quote says is that Cranston is pretty sure about where Walt is headed. He seems to think he'll end up dead by the end of the series, either from the cancer or "something else". This certainly meshes with Vince Gilligan's views on karmic justice within the show. It seems only logical for Gilligan to show us the consequences of Walt's actions. What other justice could there be but death for someone who has intentionally killed 3 people and unintentionally killed hundreds, all while cooking one of the most harmful and addictive drugs on the planet?
[update]: It has been pointed out that there are several ways to interpret the timeline based on the above quote. Season 4 is not likely to cover a TV year's worth of time, as I had initially assumed. Instead, the cumulative time that has passed since the "diagnosis" that Cranston mentions will amount to a TV year. The "diagnosis" could either be when he was first diagnosed with cancer in season 1 or it could be when he was diagnosed as "in remission" in season 3.