Hearthstone: Heroes of Warcraft might be Blizzard's first foray into the TCG genre, but from the looks to the feel of it, it's as if they've been doing this for a long, long time. It's so incredibly polished that, if Blizz continues to support it regularly, it could very well become one of the most popular TCGs around. It certainly is one of the best, even in its early stages.
Pros: The physical feel of the game, well thought out mechanics and cards, surprisingly well balanced, really fun and fast paced games, lovely music, funny, Warcraft's universe is brilliantly translated into the TCG genre, plenty of viable decks and tactics for each class make every game exciting and unpredictable, diverse and interactive tables, gameplay is easy to learn-but there's plenty of room to master it, it's FREE
Cons: Inconsistent art styles of the cards,the gold necessary to build up your card collection trickles in relatively slowly (unless you pay for it),could've used more tables and avatars