Earlier today information was dropped about Sia playing a character in the MLP Movie! It looks like she will be involved in not only a couple songs for the movie but playing a character named Songbird Serenade (as posted earlier) who is a pony pop star according to The Hollywood Reporter.
Does this play into the Queen of the Hippos description we heard about earlier and talked about in the comments on the live blog post and our followup? I guess we'll find out sometime down the line!
Thanks to ScientistDog for the heads up!