I have the FZ2 and the FZ3. The FZ3 has a better AF system, by far less purple fringing (Panasonic did a good job here!), and manual exposure as well as some useful scene modes. IMHO the FZ3 as a whole is better. What I like more about the FZ2 is the more professional look and feel and less noise in the pics.
For a FZ3 shot, look here: