Today the new Oracle Data Miner tool has been made available as part of the SQL Developer 3.0 (Early Adoptor Release 4).
The new ODM tool has been significantly redeveloped, with a new workflow interface and new graphical outputs. These include graphical representations of the decision trees and clustering.
To download the tool and to read the release documentation go to
http://tinyurl.com/62u3m4y
If you download and use the new tool, let me know what you think of it.