Enterprise Java Tech Tips instructs this week on Persisting Model Components with JDO. Start learning JDO, cause soon this spec will be deprecated [blink/]. Update: I would like to comment the comment of Doug [smile/]. I agree with you that JDO is not deprecated and there will be more code written till that moment (the moment the common persistence spec is out, the moment the first implementations are released, the moment the first dev guys produce the first well done solution and so on). I know all of these, but I wouldn't choose to publish a JDO intro article a few days after an important announcement about persistence was made. I understand that Sun guys want to transmit a "stay calm" to the actual JDO involved people, but I believe the moment for attracting new users is wrong. Because at the moment the persistence spec will be out JDO will be deprecated (this at least is my impression based on the first draft of EJB3 spec). The EJB3 draft persistence solution is based/uses many ideas taken from ORMs (as Hibernate, TopLink) and these solutions, even if at surface don't look not so different from JDO, they are in fact way too different.