The plan is to check in the initial source contribution this week.
We are still working on a few technical issues related to the ANTLR
upgrade and XML parser change. Once these are resolved we should have a
build and test process in place so we can produce a 0.1-incubation JAR for
early adopters to start using. I will provide updates on this as they
become available.
As far as getting started sooner using TopLink Essentials from GlassFish
is a good place to start. It offers a compliant JPA implementation and
will offer an easy upgrade path to EclipseLink.