Appearing on GitHub is a new exfat-nofuse project. This is a Linux non-FUSE read/write kernel driver for the Microsoft exFAT file-system.
The state of Microsoft's exFAT on Linux has been crap. The exFAT FUSE driver suffers from slow performance and isn't widely shipped yet. The exFAT support has been implemented via a file-system in user-space since it doesn't stand chances of being merged into the mainline Linux kernel over patent concerns.
With exFAT being a legal mess for Linux, the adoption of this superior file-system to Microsoft's FAT32 isn't too good for open-source fans. This new file-system supports read and write operations and is for the kernel, which should lead to better performance. However, it still doesn't stand a chance of being merged into the mainline Linux kernel due to the legal limbo of exFAT.
This code is just being distributed as source and as an out-of-tree kernel module. This module right now will work on the Linux 3.8.11 kernel but the module's author says right now there are issues if using the Linux 3.9 kernel or newer.