If you're following the apple-java mailing list, you'll see this isn't the (supposedly) the plan. They're contributing eAWT and eIO to openJDK, plus assisting in writing a new OpenGL based Swing backend and Swing lightweight placeholders for AWT components.
To quote Mike Swingler (Apple java engineering):
"Cheers all, we look forward to working with you in public!"
Sounds like the plan is to continue Apple's work as part of a respected open source project. Compared to developing in secret like they have been, what's not to like about that?
This allows them to still be behind it without having to actually do the work.