Here is how things are supposed to work. Sun created a specification for JSF. Sun then created a Reference Implmentation (RI). If you were to design an app with Sun's RI and then took that code and used someone else's RI, your app should still work. There's a chance that some things might
look a little different like validation messages and things like that. But all the UI Components should be the same. This is because Sun's spec says so.
Now, if you moved from Sun's RI to, say, IBM's RI and then used some IBM RI specific components/features you are then tied into their RI. This also ties you into using WSAD. This is marketing. IBM doesn't want you to use someone else's RI. Sun will probably release a spruced up RI in the near future to tie people into Creator. I've heard there is no guarentee that the RI you get from Sun now could be used legally in a commercial application without licensing. Can't verify that though.
MyEclipse workbench includes support for JSF although it is only configuration support; no cool drag and drop of components like Creator.
I started out coding JSF by hand using IntelliJ IDEA. I tried Creator the other day and it just confused me.

So as of right now, IDEA will be good enough for me. The difference being, if you code by hand
you should really know what's going on. If you use something like Creator, there are a few things you can pass off as, "I guess that's just how it works" and not worry too much about it.
I am currently doing all my JSF development using
MyFaces which is an Open Source RI. It's packed with some pretty good Custom UI Components as well.
I know that the next version of JDeveloper will have JSF support. But that's all I know about that. I have no idea what Oracle is doing, but be asured they are doing something. One we have a bunch of tools available, I think you will be seeing JSF show up a whole lot more.
HTH