Comment 4 for bug 448153

I would like to add, that if it the nautilus-convert-metadata were added,
it will work only for new upgrades.

No matter if the migration was successful or not, nautilus add the
the file migrated-to-gvfs into ~/.nautilus/metadata; which is verified
later to decide whether to run the converter program or not. Hence,
if the program is installed and the user already ran Nautilus 2.28
from Ubuntu it will not migrate the data.