I have couple of questions about upgrades:
Why is Ubuntu still including the release name in the
sources.list? The package manager could get this information from
/etc/lsb-release. And it's really not necessary to change this file every time one upgrades.
Is there a way to list packages installed by the user? It would be useful to be able to quickly install everything one had installed in previous releases, without installing system level packages that are no longer used by the distribution (such as hal).