Richfaces: stable and well thought out but slow development process. Massive mistake in leaving
out key components from v4 release. Nonetheless a leader.
Icefaces: Candy shop. Basic components available for free or get your credit card out. There have
been questions asked regarding performance.
Primefaces: futures that you thought would take six months take two weeks, but in the greater
scheme of things? Easy setup and good performance.
ADF Faces - possibly the best but unless you use jDeveloper you won't easily know. Also has a JSF
implementation not tied to the spec.
Maven please?