Gaming's Best Open Worlds

NowGamer has put together a three-page editorial that profiles what they feel are the "best" open worlds we've ever roamed through while playing a video game. The first 25 years of video game history is completely overlooked, which means that Fallout 3's The Capitol Wasteland, Oblivion's Cyrodiil, and World of Warcraft's Azeroth are the only RPG worlds worthy of a spot:
Anyone who has sunk considerable time into Oblivion will agree that it deserves to be included on this list. Cyrodiil is rammed to the gunnels with interesting inhabitants, detailed environments and no end of side-quests to embark on. The lush countryside is pure eye candy, but can suddenly turn eerie at night when a violent storm kicks in. One of our standout Cyrodiil moments has to be when you try to rescue a man from a painting by entering it, stepping into the colourful, abstract world that lies beyond the canvas. It is perhaps most memorable for the landmark moment when you first step outside the initial dungeon and into the sun drenched countryside.
The fact that none of the games mentioned are more than several years old is pretty telling of the author's video game experience.