There's even a chance there will be a wild contortion of the plot so that Walt's effort to protect someone in the flashforward is foreshadowing his makeshift redemption.
Jesse? He'd come back from witness protection/fleeing from a rival drug manufactuer/hiding from the law to protect Jesse, maybe? That's the only scenario I can envision that makes even the slightest bit of sense character wise. Question is, does Walter give enough of a shit about Jesse anymore? At this point, I wonder if he'd let Jesse take the fall for the whole enterprise if it would help Walter escape prosecution.
I keep thinking even Walter wouldn't stoop quite that low, but if he's keeping that ricin around behind the bedroom's electrical outlet, (possibly to use against Skyler) maybe he would. Another alternative--having killed Skyler, lost his children and having to run from the law--or his cancer has returned after all this has happened....maybe a dying Walter wants to commit one last, non heinous act and decides to get Jesse out of danger and/or trouble? Too schmaltzy, or do you buy it because of the great, twisted chemistry of Cranston and Paul? What was the point of Walt's freudian slip mumbling, "Bye, Jesse" to Walter Jr. when he left his beaten father in his bedroom? On some extremely selfish level, perhaps Walter still gives a damn about Jesse?
Walter seems to evolve and mutate every week. I can't tell about him anymore.