It seems like a new ballet/dance set will be coming out in the near future. Photos of this potential new set leaked recently and feature several pieces, including dance shoes, pink tights, pink leotard with attached skirt, grey top, ribbon headband, and grey leg warmers. I don't know which line this outfit will be for. It is most likely for the Truly Me line, to replace the current set which is broken into 2 parts. I have added it to the Master List of Leaked AG Releases. :)
Link to Master List of Leaked AG Releases: http://lissieandlilly.blogspot.com/p/leaked-ag-releases.html
You can see the plastic oval AG ego tag stitched onto the leotard at the waistline. This tag is usually reserved for their Truly Me line outfits.
Grey sweater top
Pink ribbon headband
I like the look of this new set much more than the current 2 part dance set. I really disliked that American Girl broke the dance set into 2 outfits, and put together, it seemed wildly overpriced to me. Hopefully this will just be one outfit. ^_^
Link to Original Auction: http://www.ebay.com/itm/Doll-Clothes-For-American-Girl-18-Inch-OUTFIT-/252627123029