I'd say Fallout new vegas I loved Fallout 3 and I'm sure it will be a solid game. I played fable but dont really think it will be as solid as fallout :D

Mass effect 1 and 2 have great stories. The gamneplay of both are pretty solid. I prefer mass effect 1 because its a true rpg and also because im a rpg motivated game. Mass effect 2 in my opinion is a shooter with rpg elements where mass effect 1 is a true rpg :-)