Many have commented on Oracle buying BEA out there in the blogging community. One thing I am very interested in seeing is which persistence mechanism is supported if they choose one. Most likely, we will see Oracle pushing BEA's App Server. TopLink has had a long history as a persistence provider and supports JPA. But BEA's App Server is based on OpenJPA (more specifically the Kodo product they purchased from SolarMetric.) IBM also built its JPA provider(available via the EJB 3 Feature Pack for WebSphere) on top of OpenJPA. It should be interesting to see which way Oracle/BEA goes with in persistence.
I recently released a tutorial on using the EJB 3 FP for WebSphere.