There is talk of new Open Source project to develop an application to migrate content from one CMS to another. The Exorcist is for content what ETL (Extract, Translate, Load) tools are for data. The design of the application uses custom import/export plugins that that are installed on the source and target repositories and translate content into an XML format that can be read, translated, and written by The Exorcist. The application then does XML transformations from what the source plugin can write to what the target plugin can read.
At present, The Exorcist is still a concept which has been presented in blogs and at various conferences. Initial development will be for the Midgard Framework. As of this date, there is no project site for the project.