I've had the chance to ride both the new and old (04/5)122 flx models and can tell you that they look and feel different.
graphics are completely new and different, foot pads are the same, all board holes are the same, foot straps are new adjustable and surprisingly comfy* given the large ammount of adjustability*
foot strap washers are stainless vice plastic. boards are the same dimensions width and length but new model has a concave
bottom, and probably different rocker profile ( hard to tell as there both pretty flexy)
ride, The ride straight of the bat, with the same fins on both boards, and basically only the rocker and foot straps being different, is noticibly different. The board feels like it tracks a lot straighter, and the landing of jumps seems a lot firmer, with the board backing up your landing a lot more vice sliding out a little( which i found the old model did a bit). Basically the whole ride seems a lot " firmer " and the board maintains its direction and avoids sideways slippage better IMO than the last one.
* Comfy and adjustability may not be real words, i think i just made them up.