Charlie Berger has recently put together a video demonstrating the new Oracle Data Mining tool.
The link to this video is
The video gives a demonstration of some of the main stets in building and applying a classification model. He also demonstrates applying classification to the same data.
The new ODM interface is due to me made available within the next month or two on a limited basis initially and will be part of an Early Adopter (EA) release of SQL Developer 3.