The new reward system arriving in 1.4 took me by suprise. Not only does it bring in a heavy dose of lore, but it looks bloody good. Not only does it add much greater depth to "dailies", but there's an emphasis on choosing exactly what you want. Besides this, there's still the draft and leaderboard additions, balance changes and matchmaking improvements. If that wasn't good enough, there's tons of new rewards as well as a brand new Champion. All in all, it looks an incredible update. Full notes here.