As you could see from wiki pages with our meetings follow-ups and pages about 4.0 - first 4.0 Alpha release will contains only core a4j components and in general we will works at framework stuff and CDK stuff. And them we will port the rich components stuff into 4.x. So it will takes some time and if your project is has short estimations it seems easier to create it using 3.3.x stuff and then port to 4.x after the 4.x state will be satisfactory according to your requirements.
but if you will choose to start with the very first versions of JSF 2 and RF 4.x - all your feedback will be greatly appreciated! :)
Well said Ilya, and I agree.
It really depends on your requirements in both time and maturity. RichFaces 4.0 will have useful BETA's in several months (not naming a specific month yet), and GA some time after that. 3.3.X is mature and will be going into maintenance mode ( give or take community patches, issues, etc... )