The brand new Ubuntu 12.10 Quantal Quetzal just released today. For those who need a newbie guide on how to upgrade Ubuntu 12.04 to Ubuntu 12.10, please follow this guide.
1. Open "Update Manager"
2. On the bottom left corner of Update Manager window, click "Settings"
3. Go to "Updates" tab and set "Notify me of new Ubuntu version" to "For any new version"
4. Please manually check for update to get a notification about new release of Ubuntu
5.Well, you will get a notification about new release, click the "Upgrade" button to proceed.
6. Please sit back while the Update Manager is updating your Ubuntu version
Regards :)