I had one blessedly annoying time trying to upgrade to 13.10. Every time I did a 'do-release-upgrade -d', the process would abort due to "pre-release software already installed". If you have xorg-edgers ppa repo in your source.list, you might want to:
This happens to me every single time, and I spend hours racking my brain, trying to remember what I did "last time".
Code:
sudo aptitude (or apt-get) update sudo aptitude install ppa-purge sudo ppa-purge xorg-edgers sudo aptitude update sudo do-release-upgrade -d