I have a theory- it is free and may be worth what you paid for it.
Since the first episode of last season, we know Walt will come 'back' to New Mexico incognito, buy a machine gun (that right there boys is a good ole' M-60 with at least three ammo boxes). At first it looked like Hank was going to slam Walt but now it looks like Walt may get away with it. Jesse is a little cranky sure but Jesse vs. Walt just isn't much of a contest. Suppose Walt and family 'evaporate' to New Hampshire', blend into the local area and live a peaceful life? Then perhaps something hits the paper about his old company and old comrades having some kind of shindig- we know that would get Walt's blood boiling. Maybe he goes back to Albuquerque to get even with his old partner and girlfriend and none of it has anything to do with the DEA, family or anyone else? Perhaps the company ('Gray matter' if I remember right) is having an outside 'picnic' on the grounds of the estate we first saw early on in season one.... and Walt decides to raise a little hell from across the valley with that M-60? When it is all over, maybe the authorities go searching the area of the 'incoming' and find nothing but a smoking machine gun..... and the series ends. It would be well w/in the Breaking Bad world to have that happen and the actual ending is left open to interpretation.
Did Walt and family get away?
As far as Jesse goes, he is getting in between Walter and what Walter wants, which has historically been a bad place to be. The odds of him besting Walter are slim at best IMO. Walt may 'side step' him or "send him to Belize" but at any rate, I don't think Walt Vs. Jesse will be the series ending point.
Brian
Ignoring those infatuated with flatulence, I got addicted in season 2, and have now afflicted the better half as well. We're hoping for Jessie to get through, but I think they tipped their hands in the opening scene. Walt, still alive, and going after someone, with everyone else dead and buried.