JRebel 3 is finally out!  http://www.zeroturnaround.com/news/jrebel-3-0/

I have attached a very detailed tutorial on how to use JRebel 3.0.1-SNAPSHOT with Seam 2.x hotel booking example deployed on JBoss AS 4.2.x.  The tutorial demonstrates how to add a local interface method to the HotelSearchingAction SFSB as well as adding an @In annotation and hot redeploying both changes without a build/redeploy of the EAR and/or server restart.

If you find it helpful, I can create a screencast demo of this tutorial as well.  In the future, I will be doing a similar tutorial for a Weld example.

Enjoy!