
Many role-playing games put the emphasis on 'game', but Bioware's Dragon Age Origins is putting the emphasis squarely on 'role-playing'. Not only is Dragon Age shooting for a richly detailed world with strong story elements, they are aiming at a story that changes based on the player's actions.
Don't worry, the traditional aspects of a good computer role-playing game will be present. Dragon Age will feature interesting classes, cool items, and a lot of great battles. With the ability to control multiple characters, it will also employ some great strategic elements.
But there is definitely an emphasis on story.

This fellow got himself into a bit of trouble when he stole the key to a treasure chest. After getting some Circle wizards drunk, he stole the key and tried to sneak to the chest, but was caught in the act. He's offering you the key for a bit of food.
So, how do you respond?

You can help him out, or you can just take a quick shortcut by gutting the prisoner and taking the key. These are the types of choices you'll be presented with in Dragon Age Origins, and Bioware promises that choices like this will have a real effect on the story.

The story will also changed based on what type of character you play. Elves, for example, aren't the high and noble race that many fantasy RPGs depict them as. In fact, they are thought of as a lower race and are often slaves. As such, you might have to take a little bit of lip if you are playing one of the point ears.
You'll also see changes in the story based on the class you choose, with wizards playing out a bit differently than fighters. Add them all together with the story changing based on race, class and actions, and you get a very replayable experience.