Originally Posted by
CosmicGuitars
As other users of this very forum have discovered, it's very likely we won't see a trademark at all. Hearthstone was well hidden, because Blizzard registered the trademark in a country called Swaziland, before it was transferred over to the United States after the announcement was made, allowing Blizzard to surprise us with the game and it's title. Swaziland doesn't actually keep a record of it's trademarks online, so there's no way for us to actually go and check what Blizzard has and has not trademarked.
It's very possible we'll actually have to wait until BlizzCon to find out what the next expansion will be. Shocking, I know!