who is to say this will be a musical?
as for BO potential i don't really see it other than it being a Hanks vehicle. If no1curr about Elton John then certainly even more people don't care about Elvis.
The description of the film is that it "will explore the life and music of Elvis through his complicated relationship with his manager Col. Tom Parker"
I think this is told from the perspective of Elvis's manager. Tom Hanks is the main character.
Also Elvis first started shagging Priscilla when she was 14? Wow. Didn't know that. Yeah no way that is in the film, well if it's told from elvis's manager perspective then they can just not include it.
That being said, Baz Luhrmann did direct Romeo and Juliet, and juliet is 13.... so who knows!