[Timo]

100yrs, eh?

2105.

I reckon humans would have programmed computers in such a way as to let the computer create brand new tunes by itself based on formulae that relate to known human-emotive elements of music. The resultant tunes of which would be perceived as catchy, fresh, and enjoyable to listen to.

However, I don't now think there are many, if any, new genres to be 'discovered'. Before now, genres have seemingly come about due to new technologies being found, or slowly introduced over a long time line.

To put it crudely, in order of discovery, something like...

Crude resonance > drums, percussion, etc.
Tuned acoustic resonance and/or Mechanical > Piano, strings, organ, etc.
Electricity > amplification (guitars, PAs, etc.), analogue synthesis, effects, sampling/recording (vinyl, tape), mixing, etc.
Electronics > digital synthesis, extensive sampling and sound manipulation, computers and computer processing/sequencing, sound simulation/modelling, total recall, etc.

I don't think there's anything as revolutionary to music than the introduction of electricity/electronics was back then, for us, that might happen in the future in such a way as to create completely new genres.

Instead, I think time will just see cross-matching and refinement of current techniques and genres.