The Codebase Notification Centre has always allowed administrators to setup various callbacks which are triggered when events are carried out within the application. Git & Mercurial users can already setup notifications each time they push their repositories, but now Subversion users can get in on the action. Just head over to the notification centre and setup a "Commit to Subversion Repository" notification.
You can choose from a variety of different protocols including Campfire, JSON POST and email. Full details of the JSON data which is included can be found here.