At the end of 06, assuming JP makes every start, he will have played 24 NFL games. Even then, I don't think you can make a definitive opinion on JP. I think in 07 you will learn what you have with JP. QBs take time and you will see progress, but you won't be able to fully judge JP until after 07.
Look at some of the guys from non-major college programs (or ones that didn't have a pro offense like USC) who have taken a couple years to develop...Hasselback, Favre, Pennington (pre-surgeries), McNair, Trent Green, Plummer, Leftwich and Bulger.
Everyone is looking for the next Marino, Big Ben or Palmer. There is a reason these guys are so rare, because it rarely happens that way. More likely is that in 2 years, with steady playing time, we'll know what JP is all about as a QB, and whether he can get the job done.