unionfs is something that allows the user make changes to the read-only system. Actually, it "overlaps" a read-write RAM filesystem over the read-only loopback (compressed) filesystem from CD. This would allow the user to even emerge things onto the live-cd itself. Just as an example, System Rescue CD, which is a live-cd based on Gentoo, is now using unionfs. I can understand that such huge change might add yet another delay to the final 2008.0 release, but I believe this will be very useful for the final user, and should not be forgotten. I've reported it here: http://forums.gentoo.org/viewtopic-p-5122604.html#5122604 And also commented about this here: http://my.opera.com/CrazyTerabyte/blog/2008/06/11/installing-gentoo-linux-amd64-on-my-notebook
Not unless it hits the mainline kernel. We tried UnionFS support and it was so difficult to keep up with it, due to it being *very* kernel version specific.
