Activision Blizzard released their earnings results for 2015 today (required for listed companies), and there was an interesting blurb about how Hearthstone is performing (full report can be found here):
On November 6, 2015, Blizzard Entertainment revealed that Hearthstone®: Heroes of Warcraft™ had surpassed the 40 million‐registered‐player milestone. On November 12, 2015, Blizzard launched The League of Explorers™, the third adventure for the franchise, with 45 new cards. This Adventure sold over 20% more units as of the first 6 weeks after launch than the prior Adventure in the same time frame. As a result of this new content, and continued strength across platforms and geographies, Hearthstone hit all‐time franchise highs in multiple categories, including MAUs, at the end of Q4.
Do keep in mind that registered users is an accumulated number, and does not represent how many players are currently actively playing the game (if that is the case, then World of Warcraft would still be the most popular game on Earth right now!). However, by indicating that its Monthly Active Users (MAUs) are at an all time high, it does indicate that the game is more popular than ever right now. With momentum around Hearthstone as one of the leading eSports titles and with more high profile individuals playing the game (such as Poker star Daniel Negreanu), I can only expect 2016 to be an even bigger year for the card game… unless they really botch the transition to Standard Mode and make unnecessary rule changes, which given the team’s track record I high doubt will happen.