Just came across this interesting post by Rogers Cadenhead which shed's light on Virtuoso's xmlStorageSystemAPI() implementation which is available as a live demonstration on our demo server machine (alongside many other demos -- there are OPML, OCS, and RSS feeds for these funcitonality demos/tutorials). Commercial Server Supports Four Weblog APIs Virtuoso 3.2 will be released in beta form latter this week or early next week, and it extends the Weblog Functionality aspect of Virtuoso to include the following: Tracbacks and Pingbacks CommentAPI Subscription Harmonization Atom The new release will include an Weblog Platform module that offers the Virtuoso equivalent of Moveable Type or pMachine, the fundamental difference being that Virtuoso's storage is database independent and the application layer is developed using the Virtuoso's web application development languages (VSP and VSPX).