I strayed from the 'one-true-path-that-is-Ubuntu' (joke! ;-) ) and
tried Mandriva, Suse and Fedora recently and, despite having a separate
/home partition, ran into problems - basically, two of the distros (I
*think* Mandriva and Suse, but I don't rightly remember, this being a
short while ago and me being slightly the worse for alcohol at the
moment, sorry) set the user ID to a different number than Ubuntu had
used so, despite the fact that I set the same user name, I couldn't
access any files - a problem solved by a quick visit to the terminal and
a 'chown -R' - only the third distro had the intelligence to see that
the user names were the same despite different UIDs and offer to
transfer ownership.