This is a 'testing' version which sits between the stable release of v10 and the still in development v11. The most recent beta is 10.1 beta12 and as it says on the download page "Warning: We decided to discontinue the v10.1 branch before it was release-ready, the functionality here will now be delivered in a longer-term branch, v11. Use v10.1 only for early testing of selected new functionality."
The best way to see what has been added to this version is to browse the 10.1 branch of the Github repository.
The best way to see what has been added to this version is to browse the 10.1 branch of the Github repository.