"I'm pleased to announce another release of Squashfs. This is the 22nd release in just over five years. Squashfs 3.3 has lots of nice improvements, both to the filesystem itself (bigger blocks and sparse files), but also to the Squashfs-tools Mksquashfs and Unsquashfs," stated Phillip Lougher.

Squash developers are focused next on getting squash into the mainline kernel.
http://kerneltrap.org/Linux/Squashfs_Aiming_For_Mainline_Kernel

22 revisions and five years. I've only been working on getting the Digispeaker patches in for about a month.

Good thing squash is going in, we use it for our root flash file system.