Heroes of the Storm is a MOBA with a twist that is both highly accessible to the newcomers, while offering plenty of depth to the veterans of the genre.
Pros: Fun to play, no fluff, a good number of heroes with vastly different playstyles and builds that fit each hero, mostly well balanced, a good number of arenas with different objectives, promotes and relies on teamplay over individuality, great visuals and sound, matches are usually over within 20 minutes, most matches can be turned around up until the very end, solid tutorial, plenty of ways to test a hero, if a player disconnects a decent AI will replace him/her soon after, daily quests, you're in a game within a minute of picking a hero, Blizzard's level of polish, it's FREE
Cons: Half of the heroes (and all skins) cost an absurd amount of gold/real world cash, no way to report a player within the game, some heroes are slightly overpowered, while others are underpowered, there's no grid with party members' health