Rainbird on 15 February 2010
Tough one.
Flower is a given though.
Other than that, I'd probably say Mirror's Edge (I love the movement, inFamous and Assassin's Creed add to my love for this) and then there are games like Uncharted 2, God of War 2 and others, that are intense, high quality singleplayer experiences. Finally, I'll add Heavy Rain, just because I know it will be on there 
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