Have just seen it. While I concede that an element of fiction may be necessary in a good biopic, I'll leave you to judge the facts of this one. (Those concerned about spoilers look away.)
The movie shows the emergence of Miles from his stay-at-home phase to present a previously unheard sound - his electric period. (OK on the dates so far? )
Miles, at war with the world in general, has one buddy throughout the movie - a Scotsman played by Ewan McGregor. As Peter Bradshaw writes in today's Guardian: "McGregor is arguably yet another example of the white partner that Hollywood requires of its African-American stars." Miles must be turning in his grave!
The seeds of the new sound are contained in a tape and Miles takes the final leap from the sounds on the tape via the assistance of a young trumpeter called Junior to achieve the electric period sound. (Don't even bother to check the biographies.) At one stage music industry baddies steal the tape, leading to a car chase and shootout.
Well, at least there was some nice music on the soundtrack!