The leading change with this release is a "major performance improvement" in the area of 20% faster for small files along with large files testing in a controlled lab environment. More details on this Gluster 10 performance work and some of the numbers via this ticket .
Gluster 10 also has improved start-up times by randomizing the port selection for bricks, other performance improvements, and a heal time improvement with larger window size. There are also many bug fixes and other smaller improvements for this distributed file-system solution.
More details on Gluster 10 via Gluster.org .