I think today's gamers are not really interested in "getting better" at the game. They're more about the story or playing online.
I love to get better at games, especially ones like Contra 4. Topping their high scores, beating them with one credit/life, but in the end, only other gamers like yourself won't see you as a nerd. ("Playing against a soulless computer? what a waste!")
I don't care what they think, though. Lately I've been playing a lot of Contra 4, Reaxxion, Arkanoid DS, Puzzle Quest, Every Extend Extra Extreme, and Geometry Wars Galaxies. I'm so addicted to them I have left games like Mass Effect, Assassin's Creed, Call of Duty 4 collecting dust.