There is a in-game advertisement for the upcoming drama premiere, The Mob Doctor. Zynga have 'updated' the image of the default Power Packs to the Mob Doctor Power-pack image. Banner can be seen below. The mentioned drama airs on Mondays at 9/8c, premieres 9/17 on FOX.
These newly updated Power Packs seems to be temporarily replacing the default Power Packs. Use the packs to refill your Stamina or Health. There seems to be no difference between the default packs or the updated ones.