Well, I kind of agree with the previous poster...and I kind of don't. Currently, there is one server that directly implements JSF 2, and that is Glassfish 3. Don't expect support in any other server for some time...eventually,
JBoss will have it, and Weblogic, and far (FAR) down the line Websphere.
Tomcat can run JSF 2, but it's not a complete application server.
So my feeling is: current JSF production will be focusing primarily on JSF 1.2, certainly for the next year, and maybe longer. But JSF 2 has some very nice features, and if you can target Glassfish or Tomcat 6,
you should definitely go that route.