I really liked the different intro stories for Dragon Age. The dwarf ones were just great. The world was incrediblely filled out. Even minor quests like the dwarf chantry felt like they made a difference. The battles were challenging (at least on a PC).
Greatest of this generation is a matter of taste in various areas (art, story, immersion, gameplay, etc). I tend to prefer sci fi so I liked Mass Effect's story more. I like Final Fantasy's art style more as well. I was not a fan of Demon Souls. These are all personal opinions thou.
In the end, Dragon Age is a great rpg that I enjoyed playing. I would not rank Dragon Age as the best this gen but I have friends that definitely do.