Will Scorsese's Sinatra Biopic Have Multiple Franks?

Martin Scorsese had this to say to reporters in India about his long-aborning Frank Sinatra biography: He'd like Al Pacino and Robert De Niro to play Ol' Blue Eyes and Dino. But would the veteran actors play the Rat Pack-era movie stars/saloon singers and Scorsese would cast younger performers to play Sinatra at earlier stages of his career, as Todd Haynes did in his unconventional Dylan biopic I'm Not There? The Playlist suggests that this might be the case. (Hat tip, Anne Thompson).

Who could play Young Blue Eyes? Zac Efron and James Marsden have the stage presence (and nice voices) Justin Timberlake has the stage presence and The Voice and Leonardo DiCaprio has the inside track with Scorsese, with whom he's made Gangs of New York, The Aviator, The Departed and Shutter Island. Who would you cast?

And on the subject of Sinatra, who passed away twelve years ago, name the definitive Sinatra movies and songs.