How do I find a list of packages that are outdated and need to be upgraded using aptitude?
I am using Ubuntu 10.04.
Another way to achive that from the command line is that of apt-show-versions.
The man page states:
apt-show-versions parses the dpkg status file and the APT lists for the installed and available package versions and distribution and shows upgrade options within the specific distribution of the selected package.
Once you've installed the package:
$ sudo apt-get install apt-show-versions
the only thing you have to do is:
$ sudo apt-show-versions -u
Hope that helps