How to upgrade Ubuntu 10.04 (Lucid Lynx) Server to 10.10 (Maverick Meerkat) Server

Install update manager
$sudo apt-get install update-manager-core

Change in release-ugrades file so that it says Prompt=normal instead of Prompt=LTS
$sudo vi /etc/update-manager/release-upgrades

Finally start the upgrade and answer yes [y] on all that is asked
$sudo do-release-upgrade

After the reboot you have now a 10.10 version running instead of 10.04