SystemRescueCd 4.9.1 is the first point release to the 4.9 series, which was initially announced at the end of October 2016, and it ships with new kernels. While the standard one was updated to the long-term supported Linux 4.4.39 kernel for both rescue32 and rescue64 editions, the alternative kernel is now Linux 4.8.15. Linux 4.8.15 also happens to be the latest stable kernel release that most GNU/Linux distributions ship with, and SystemRescueCd now uses it too for the altker32 and altker64 versions. Apart from that, SystemRescueCd 4.9.1 includes updated file system tools like btrfs-progs 4.8.5 and xfsprogs 4.8.0.