We just released the brand new Hibernate Annotations module as an alpha version. This module provides the Hibernate facilities to declare Hibernate O/R mapping metadata through JDK 5.0 metadata annotations (instead of XML mapping files or XDoclet preprocessing). We have implemented the EJB3 (JSR-220) O/R metadata annotations defined in the early draft 1 of the spec. This set of annotations covers all common mappings cases.
Next step for us is to provide custom annotations to cover Hibernate specific features while following the EJB3 spec evolutions.
This tool is designed for easy-of-dev and quick application development (mapping metadata in the sources, no preprocessing step, configuration by exception minimizing the metadata declarations). Give a try to this new programming model. Feedbacks are welcome, especially on the Hibernate specific features you want to see covered by annotations.
Download it and have a look at the tutorial and the comprehensive test suite. It will give some good samples.