A Bay area source says that Durant's most likely destination outside of OKC is.... the Bay area?! Shocker!
More seriously, though, even if their Finals loss opened the door for this to happen a bit, I still just can't imagine that it actually does. Durant just does not strike me as the type to do something like this, and, frankly, he'll justifiably lose his status as a top-3 player in the game if he does.
You just cannot join a team in this context, i.e. the greatest regular season team of all time, three All-Stars, 2x NBA MVP, and not do damage to your legacy. And it will be justifiable, too, because he'll essentially be admitting that he cannot be the top-dog on a championship team.
And if it actually does happen, I'm going to go out on a limb and say the fit is less than ideal and there are chemistry issues in the locker room. All three of those guys in the prime of their careers will lose a SIGNIFICANT amount of touches, and their offensive statistics across the board will go down.
BOLD PREDICTION - if he actually does join the Warriors, they will not win a title next year. They need another Draymond Green-type player before they need a primarily offense-only player in Durant.