cura on 02 January 2010
uncharted 2 is a lenghty single player game (by today's standards that is) with a decent multiplayer component.
valkyria chronicles also has a meaty single player campaign.
I haven't played it yet, but demon's souls is meant to be pretty long also.
Infamous is another one, especially because you can play as 'good' on one playthrough and 'evil' on the next.
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