I missed this back from January. Late Night Software released an XSLT scripting extension for AppleScript.
- It’s built on top of Xalan-C
- It understands the xml-stylesheet processing instruction
- It also supports straight XPath queries into an XML document
- You can write extension functions for it in AppleScript
Since it’s easy enough to get to AppleScript from the shell or Script-aware-applications, this makes a nice avenue for you to add XSLT to your applications without the hassle of building an XSLT library.