that freaks me out too... this is spn, anything can happen. and i'm frankly ready for the ride
and i think the future was CANON, because of the decision that dean made during that phone call to sam
but now that dean and sammy aren't splitting up anytime soon again, i honestly don't think lucifer and michael are getting in. 1) it'd be a cop out. 2) where's the growth in that? sam just saying yes after everything? and come on dean? yeah. NEVER going to say yes. it's not HIM. so i think the future he saw was CANON, but i think because of everything that's happening so far... i think/hope the winchesters can change that future