The January 2013 edition of Toyworld Magazine has the playset above listed on it's 211th page. It does seem to be depicting an alicorn that matches Twilight Sparkle's color, but there is always a chance its another pony entirely. The actual location it's featured in doesn't say anything other than "For My Little Pony, Crystal Empire launches in 2013".
I'm sure more information will pop up eventually, but until then, have fun speculating!
Thanks to.. Twilight Sparkle for the heads up and article link!