We actually had this submitted a bunch today, mainly people freaking out thinking it was an ad for season 3! Time to clarify it for you all at once!
This is actually new ad for the upcoming MLP Comic slated for a November release date.
Still, its worth getting excited over anyway! They aren't copying episodes with these, so technically its even more pony for us to drool over.
Thanks to Nom de Pony for the image.