Comment 2 for bug 57631

Edgy appears to have a similar problem with LVM.

Installing from the daily Kubuntu PPC Alternate CD, I accidentally chose "Erase and use LVM" instead of "Partition manually". This trashed my data with no apparent way to recover. (Thank goodness for backups!)

Other irreversible choices (such as the regular erase-disk option) prompt for confirmation that such-and-such partitions will be formatted. If a mistake was made, the user can choose "Go back" and then "Undo changes to partitions" to recover. With "Erase and use LVM", the new partition map is written to disk before the user is asked whether to format.