My understanding is that Sync 3 will run on Sync 2 HW. And if an update to the APIM is needed it would be covered under our "extended" 5 year warranty. But you probably would have to prove that Sync 2 was broken in some way in that regard. I personally hope it's just a download and update SW type of deal.
Proving that Sync, was broken? Some might argue it was broken from day one. I've had a love hate relationship with it. Other than the regular drops I experience with it (music via bluetooth) it works pretty well for me now.