Hi
As the Java Server Faces specification states
It is understood that many of the problem spaces targeted by this JSR are already being addressed in other projects. One prime example of such a project is the Jakarta open source project, Struts. However, this JSR is aimed at creating a standard for Java server application GUIs, which will serve to unify what's become a fragmented area and strengthen support in tools and other third party products
I think that the Struts application is a greate model to work on. It has also been developed as an Open Source.
Sun Microsystems tends to develop things that already have become popular.
Similar is the scenario for the logging api. Where as the Log4j from apache is a good logging api by itself, Sun has introduced its own logging api in jdk1.4.
Lets see what Java Server Faces has to offer and then decide what to choose visa vis Struts.