I don't think all of these decisions (regarding the future of Struts and JavaServer Faces) have been made by the Struts Project Team yet.
My current understanding is that a set of integration class which implement the JavaServer Faces spec will be made by wrapping existing Struts components. Therefore, existing Struts Applications will function normally, and moving forward developers could code against the
JSF API instead of explicitly using the Struts classes. However, I would be highly surprised if the first version of JSF has anywhere near the functionality of the current version of Struts and I wouldn't be overly surprised to see many stick directly to Struts. Typically, the first version of any spec is a bit weak, however JSF may be a bit different since it is being led by Craig McClanahan (the creator of Struts).