MSW is reporting that Max Von Sydow's character has been revealed to be a Jakku elder named Lor San Tekka, who knows the whereabouts of Luke Skywalker.
In the article, it is cagily implied that MSW knows more about the character but will not reveal it. So, hope springs eternal for the Boba Fett rumor.
Someone on Reddit expressed his hope that this character name is not some reference to another JJ Abrams film or show. I heartily echo that sentiment.