I was never big on open ended games growing up. I preferred to play games that had a strict goal at hand. Save the moon, beat the bad guy, save the world. Typical Rpgs. When i started working at Game Stop I learned about Fable. The game was just released and the main tagline was "choose your own adventure". Thought it sounded kinda cool. I bought the Xbox and 13 hours of game play later, the game was complete and I already had a good idea what the adventure would have been if I chose to be evil.
I won't deny that I was disappointed i spent 250 bucks to play the game. I wasn't big into Halo yet, so I felt like I had made a pretty big mistake. My brother showed me a game he had that he enjoyed. It was Elder Scrolls III: Morrowind. The map size is approximately 10 square miles and there are tons of quests to do. I put about 40 hours into just the thieves guild.
Several months later, I saw an article in Game Informer about ElderScrolls IV: Oblivion. Oblivion supposedly has 16 square miles. I ordered a new PC the moment the system requirements were released. It was a Dell XPS 400 and it's still my main PC at home. The game came out about a year later, I waited at Game Stop for 4 hours to get it. The shipment was delayed due to a snow storm in Kentucky. The game sat in my backpack for a week because I took a vacation to visit a lovely girl who is now my wife.
I easily put 80 hours on the game the before I got remotely bored with it. I put it down until after the Knights of Nine expansion was released. I played it again for another 60 or 80 hours. The best thing about both games is that the enemies level with you. You can me max leveled and still get your butt kicked. It really puts you in your place.
I started playing the game again recently. I realized how much I really enjoy the open ended quests. I'm a little anti-social when it comes to gaming. I play on my own terms so playing in a guild in WOW wouldn't suit well for me. I'm 100% sure that I would love the game.
Bang for your buck, this is possibly the best game I've ever played that keeps you coming back for more. I have heard that the console version of Oblivion plays better, but custom add-ons are made by players for both PC games that can add even more hours of play.
Oblivion has been out since 2006. Bethesda is a company that makes you wait for awesome games, but the wait is totally worth it. Rumors are flying that Elder Scrolls V will be announced soon. I hope the rumors are true.