I upgraded one of my Karmic servers to Ubuntu 10.04 RC the other day.
The last upgrade from Jaunty to Karmic was a rather traumatic process, but thankfully this time round all went smoothly. Not really any overly noticeable changes this time round other than a few more things have moved into upstart (MySQL for example) and when I boot via KVM the new Plymouth boot screen is present, although not sure why this is even included in a server release.
It’s about as updated a LAMP setup as is possible including Apache 2.2.14, MySQL 5.1.41 and especially pleased they put in PHP 5.3.2 after the code freeze. On this server I’m actually running Zend Server CE (which already had PHP 5.3.2) as Zend are quicker to push out the updates, but on others I will stick with the default Ubuntu release.
What else can be said about a server OS? Well, it just works 🙂