Hearthstone Rise of Shadows - that's the name of the new expansion. Thanks to a cached video upload on Google that isn't accessible, we've learned the new expansion name. Phonandroid also had some information on the new expansion which included the logo and the price for the "Megapack" pre-order which will set you back 80 Euros (65 with Amazon Coins).
We're expecting to see more details on the expansion later today, so check back! Learn more about us, HearthStation, here in our welcome post.
Thanks to reddit users trauthor and ToxicAdamm for the tip!