For me, it's pretty close between 4 games. Mass Effect 2 is the first as it was not only an amazing experience, but also because it was such a radical evolution from the original. That evolution is a double edged sword, however, as the streamlining process also removed a lot of things I liked from the original. On some levels, the game isn't even an RPG anymore.
The second game on my list is Heavy Rain. The concept behind this 'game' was simply phenomenal and I applaud Quantic Dream for doing something outside the box and pushing the definition of the medium outwards. There were some snags in the execution, however. The control and technical issues I could ignore, but there are some design issues that could have been dealt with differently, mostly relating to the multiple permutations in which the plot can advance.
Third, God of War 3 makes my list. Epic locations/bosses/scale - check. Amazing graphics - check. Controls and plays fantastically - check. Concludes the trilogy in a worthy fashion - half a check (some of the ending scenes were a little lame). Fantastic game - double check. My only complaint with this one is that it's hardly fresh. For the most part it's the same God of War we've come to expect from the other 2 titles that proceeded it.
Lastly, Red Dead Redemption. Grand Theft Auto is obsolete as far as I'm concerned. This game blew every GTA game out of the water. The world was the most believable I've ever seen. The characters were great, the story engaging and the gameplay was fun, albeit a bit dated using the GTA 4 engine. The shooting mechanics would be my only complaint about this one. But I've never really considered that to be Rockstar's strong suit. The most important thing is the world and they nailed it.
And the winner is-----------------------------------------------Red Dead Redemption!
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