It won’t make it into 5.5 (I don’t think) but as I understand it, it almost made it, so my guess is 6.0 right after that. Mid-this-year sometime. 5.5 is due out in March. Part of this wait is related to waiting for supporting platform technologies first, management won’t knowingly invest money into a feature we know we are just going to throw out in a year if an Eclipse project is already working on platform code for such a thing. So then we can focus on features (like how the Hibernate rev-enginerring and Spring integration work) as opposed to wasting a lot of time on plumbing code that barely benefits users.
The down side is that we need to wait a bit longer sometimes before rolling out said feature.