2K (360, PC)
It's not perfect, but The Elder Scrolls IV: Oblivion is a giant leap forward for role-playing geeks.
The game has one of the most complex character-development routines since Bioware's Neverwinter Nights. You can pick your race and change the look of your character's face with an absolutely ridiculous level of detail. You decide what you want your character to be good at and then choose the class that meets those parameters. Don't like the classes available? Create your own and give it the disciplines you want.
The game starts as you break out of prison with the Emperor. By the time you've passed through the capital city's sewers, you've learned how to use your weapons, as well as pick locks. This last skill comes in handy, as many good things are hidden behind locks.
After the Emperor's death at the hands of the agents of Oblivion, you're shoved out in the world with a vague mission to restore the rightful heir to the throne. If you follow that mission directly you can finish the game in about 20 hours. But if you decide to explore the hidden towns and ruins, you can have about 400 hours of continuous gameplay.
There are few games a reviewer wants to continue playing after the review is done, but I'll be playing this one well into summer.