You could update 12.10 to 13.04 in place via
Code:
sudo do-release-upgrade -d
The -d tells it to consider dev releases which 13.04 still is at this point. Be warned it will take quite a while as all your installed packages will get upgraded. Remember that 13.04 is intended for testing purposes only until it is officially released.
10.04 can be upgraded in place to 12.04 (LTS to LTS) using the GUI update manager and you probably want to do it before 10.04 desktop support runs out in April.