Issac has done a great service and provided a concept application to demonstrate how to move from FB3 to FB5. I won't talk about it but I wanted to make sure to get a post up about it and point you his way to check it out. I'll post a full review this weekend once I, .like you, have had a chances to poke around and look at what he is doing. His description in the post makes sense!
FB3 upgrade path