1. JSF and Struts- Craig reassured the audience that while JSF represents a major advancement in web development, Struts most certainly wasn't going away nor is it being left in the dust. In fact, Craig noted that he is currently working on a Struts-JSF integration library that will allow Struts applications to coexist on the same page as JSF components. In this way, companies with existing investments in Struts won't have to give anything up in order to make use of the new capabilities made available by JSF.
2.JSF and Tiles- Currently JSF doesn't include a substitute for Strut's tiles, although there is some discussion about standarding a tiles like taglib in future releases of the JSTL.
3. JSF and Portlets- JSF and portlets are basically complementary... portlets allow you to dynamically assemble custom portal pages using portlets, while the portlets themselves may internally include JSF components.
4. JSF and Tapestry- The spec leads expressed preliminary interest in exploring the possibility of including a tapestry like XML rendering framework similar to tapestry in JSF 2.0.