Tutorials.
Highlight ease of use, time to market.
Emphasize that JPA skills are not lost by using Ebean, that portability back to JPA is a snap if needed.
Answer blogs and your own forums.
Listen to developers. Build for them and in response to their requests - when within the vision.
Have quick updates. The turnaround attracts attention.
Programmers have more on their hands than ORM. Provide convenience and speed for development.
new Timestamp(new java.util.Date().getTime()); ??? Would the addition of a no argument constructor make sense? Your api should not be like that.
Well, focus on the people that use the software and the people will take care of your marketing.