For gamers, obsession came calling in the form of The Elder Scrolls V: Skyrim

When it comes to the sheer joy of exploring an open world, Minecraft reigns supreme. Created on a lark by Swedish programmer Markus Persson, the game randomly generates a gargantuan new environment every time you tell it to. Comprised entirely of chunky, Lego-like blocks, the world can be altered at will — dedicated players have spent hours moving blocks one-by-one to create replicas of things like the USS Enterprise. Minecraft is an impressive indie success story — first released in its alpha version in 2009, the game now boasts nearly 242 million logins per month.

What lessons will open world games learn from the class of 2011? Will 2012's vast gaming environments be welcoming or forbidding? Will players be given long lists of collectibles to hunt, or simply asked to explore for its own sake? Dec. 20, thousands of people logged into Star Wars: The Old Republic for the first time, a big-budget MMORPG from local publishers LucasArts and Electronic Arts. Not content with the vast worlds already available to them, these intrepid gamers opted for an entire galaxy — a galaxy far, far away.