Well, BMW certainly succeeds in confusing everyone with their upgrades. I just took delivery of my 2013 335 with performance power kit and M Sport exhaust. Based on this current info, I would assume the M Sport power kit to be released in March 2013 is a "different" power kit. I just wish BMW would let everyone know what the supposed differences are between the 2 power kits. Based on what I can find on the internets, the only difference may be that the installer is wearing a shirt with the M logo on it.
2013 F30 M Sport/xDrive/Black Sapphire/Black Dakota/Performance Power/M Sport Exhaust/AT/Premium/Cold Weather/Tech/19"