So you know when it flashed to the future and Walt was arranging his bacon? Well after he killed Krazy 8, he started cutting the crusts off his sandwhiches just like him, then after he killed Gus, he started acting like him, then after he kills Mike, he starts drinking the same drink as him. If you picked up on all that, then all you need to know now, is that Skyler was the only one who would arrange his bacon like that.
He buys a machine gun in the cafe and doesn't tell the Waitress his name, my guess is because he is wanted and is in hiding. I think the final scene(s) will be him attacking the DEA office and being killed by Hank. Or he is at gun point infront of the DEA, news choppers flying over, Walt being distraught having killed Skyler says his apologies and then shoots himself.