Speaking of ZFS, I'm currently setting up Ubuntu devel branch on a new laptop running ZFS. I already have Debian with ZFS on it. The datasets are zroot/debian, and zroot/ubuntu. Debian boots just fine, however, Ubuntu insists that the zpool it's looking for is called rpool and not zroot. So every time I boot Ubuntu, I need to import the pool, and manually mount the zroot/ubuntu to /root before exiting initramfs. Is there something Ubuntu is doing differently and Debian for ZFS? Both are using the ZoL packages.
Edit: Turns out Debian is happy with only the boot=zfs parameter. With Ubuntu, I had to specify the rpool=zroot and bootfs=zroot/ubuntu parameters.