For example, exp_weblog_ or exp_trackbacks? Any others? Is this something that you normally do?
I would've thought that any exp_weblog_ tables should automatically get converted to exp_channel_ so if they're still there, that would raise a red-flag with me.
Same with exp_trackbacks; if you've selected not to keep them during the upgrade process, then that table should be removed.
The only tables that should be left over would be ones that were added by older add-ons that you're not using anymore.