If you've been playing around with Oracle's ADF Faces for a while you'll probably become curious at some stage about what other JavaServer Faces (JSF) component sets are available out there. The AJAX JSF Component Feature Matrix site gives a good comparison of the other component sets that are available and the vendors or open source efforts behind them.
You'll note that ADF Faces is listed as project Trinidad. I guess as Oracle's and the Apache project diverge the matrix may end up having a separate list for both, but for now it's all under Trinidad.
One of the nice things you'll note about ADF Faces is that the component set is comparable to other's solutions. Oracle's JDev 10.1.3 ADF Faces release nearly 1.5 years ago put them way ahead in the JSF game. Here's hoping the next major release of JDeveloper will see them leap ahead again.
Just a small caveat that not all the component sets are compatible. For example ICEFaces and ADF Faces components will not work on the same page as ICEFaces requires its own ICEFaces specific treeroot view tag, which doesn't support ADF Faces components. However in this specific case you are free to use either component set on separate pages (though the look & feel of your application would be a little crazy). If you are thinking of using components from 2 vendors ensure to do some research to see if they can work together.