A component that doesn't work with both implementations is simply broken. Instead of relying on "help" from a JSF implementation, it should be redesigned to include its own help.
I don't think there would be many +1 votes for releasing new components that depend on the MyFaces implementation. I also agree with your earlier point about one or two components that don't work with RI spoils the reputation/perception of the entire component set.
Craig
Sean
