The update bumps the version of Xbox Music on Windows 8.1 to 2.6.653.0 and has the following changes as per Microsoft’s employee:
- Fixes for cloud syncing bugs
- Minor fixes and improvements
Xbox Music on Windows Phone has jumped to version 2.6.666.0 and has the following change log:
- Fixes for black screen for some users
- Fixes for issues which were preventing music sync from cloud
The update for both Xbox Music on Windows and Windows Phone 8.1 are available for download from Store and will be installed automatically. Otherwise, you can manually install the update by following the instructions in this tutorial for Windows 8.1 and here for Windows Phone 8.1.