The glittery Pinkie Pie spotted a few months back has been found in packaging. She will be part of a Target exclusive line called Pinkie Pie's Boutique.
Other additions to the line may include the glittery Wysteria found on Taobao around the same time as the Pinkie above, a Playful Pony size Pinkie Pie with black, pink, and white hair, and/or a Fashion Style size Pinkie Pie nicknamed "Black Tie Pinkie" who has two-toned hair and a matching cutie mark to the Pinkies above. Of course, we won't know for sure until the line is announced and in stores. Release date is unknown.
(Source: MLP Arena (1, 2))