Hobbsee reports this is a problem with the dependancies in 'gnome- applets' which means that gnome-applets is not even installable on feisty at the moment!, but will shortly be fixed.
** Changed in: update-manager (Ubuntu) Status: Unconfirmed => Fix Committed -- feisty update-manager error calculating upgrade https://launchpad.net/bugs/80830 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs