Just as a point of interest, here’s an example of a human-generated, heavily annotated transcription of a jazz performance:
Sancticity, Scofield solo analysis
transcribed by Bert Ligon
http://in.music.sc.edu/ea/jazz/Transcriptions/Sancticity.all.pdf
It’s clear that in the near future we’ll be able to generate a machine transcription that more or less matches this one in terms of notation. But it’s also clear that “which note, when” is just the very tip of what it might mean to analyze a performance.