TVersity is an application that is an UPnP/DNLA server that will share your content with any compatible devices. In addtion to just sharing, it can transcode the content so it is playable on most devices.
The installation was a little tricky on Windows Home Server, as you have to RDP in to the server to install it as you would on a windows computer. Also, you have to configure it to run as a service. Also, I had to configure the Windows Home Server firewall to allow connections to TVserity.
Once it was installed, with the additional codecs, I was able to play most of my videos on my Xbox 360, even our home movies that are encoded in MP4. On the Xbox, the TVersity server appeared along side the builtin UPnP server, so you can use either to play your content.
Unfortunately, every time the TVersity server scans for new content (which it is configured to do daily), the services appears to stop running. I am sure that this bug will be fixed, or I can just reduce the number of directories that need to be scanned to only the videos.