I am looking into getting a new VPS and I am just wondering what OS do you recommend. I was thinking about a Ubuntu 7.10 server.

I've always prefered Cent when setting up a server. Ubuntu is great as a desktop, but was not built with servers in mind.

Freebsd 6.x

What would be the feature that keeps you using it?

Resource efficient, stable, good community, and the repositories are chock full of server software goodness.

What I like most in Freebsd is ports collection which allows to install, deinstall and upgrade almost all popular apps in a matter of minutes and several keypresses.

What didn't you like about the ubuntu server?

I've never personally employed Ubuntu as a server. The general design philosiphy from the Ubuntu team is simply not server oriented though. They're going to be working harder at pushing out new features, where as something like Cent OS/RHEL/Fedora/*BSD is going to focus on performance and stability more than anything. I also love the package management for both BSD and Cent. Yum and Ports are both great. I've never really worked mush with Ubuntus package management (Mostly Debian apt-get, right?) so I can't say how good is is/isn't. They're probably more agressive with their patches I'd imagine....

I like freebsd 6.

centos is better in VPS environments.