On Natty x64 installed from the 18/02/2011 daily (in the last three dailies, Ubiquity locks on the first screen), /boot installed on it's own 250 MB btrfs partition, / on it's own 19 GB btrfs partition, system fully updated from main server as of 13:23 UTC today, the sparse file not allowed error message is still present so this has not been fixed, though the system remains bootable.
On Natty x64 installed from the 18/02/2011 daily (in the last three dailies, Ubiquity locks on the first screen), /boot installed on it's own 250 MB btrfs partition, / on it's own 19 GB btrfs partition, system fully updated from main server as of 13:23 UTC today, the sparse file not allowed error message is still present so this has not been fixed, though the system remains bootable.