Hi Todd
We certainly are very interested in XML processing and to be honest, we've been waiting for the DITA "wave". But it hasn't hit us yet.
Obviously, our repository and services can work with XML very happily. There are XML metadata extractors that can populate content properties from the XML content. The scripting and templating engines can manipulate XML. We also have XSL and XSL-FO transformation hooks.
If you have a DITA editor, then it can work directly on content in the repository over CIFS/SMB, webDAV or FTP.
Tell us what you're looking for in more detail and we can try and respond. If you're likely to want to take out a support contract, then there's more incentive for us to get people to help you (just reality, we have to pay our staff).
The .doc support is there because that's what a lot of people have asked for - basically, so they can use Alfresco instead of SharePoint.
Cheers
Paul.