I work for Sibelius so I'm heavily involved in this world. MusicXML is a great standard and offered a solid basis for data interchange between music notation programs. But now there's a new group working to build a successor standard, MNX: https://w3c.github.io/mnx/docs/
It was originally going to be in XML but they recently switched to JSON, which is a good move, I think. I can't wait for it to be adopted as it will give so much more richness to the data set.
It was originally going to be in XML but they recently switched to JSON, which is a good move, I think. I can't wait for it to be adopted as it will give so much more richness to the data set.