Note that this JSR is a candidate for inclusion for Java 7. In the meantime Alexander Potochkin has taken the Spec lead and worked a bit on it a few months ago but for a least the last 3 months it's again quiet from Sun.
My suspicion was confirmed by Karsten Lentzsch a well-known Swing developer and one of the member of the expert group in a dicussion in the mailing list:
"I doubt that it can be included in Java 7; and I'll vote against it."
"There's no activity in the expert group, and no visible progress in the public code base. Anyway I hope that Sun will revive this JSR. At least, it would help if someone from Sun could comment what's going on."
Also this week another comment from Jean-Francois Poilpret:
"As far as I can see, there is no active development here, and this has lasted for long now. It's a very long time we didn't see Alex in here, maybe he has been requisitioned (one more) to full-time JavaFX"
"I think that now the only way to go ahead with the AppFW is to fork this project"