Tough choice, but I'm going to go with Mega Man 9. I grew up on the Mega Man series, and I've missed the fun Mega Man feeling I'd get when I played the old games. When I played MM9, it all came flooding back. The graphics: perfect. The music: on par with the classics. The challenge: oh, man! I've only managed to beat one boss so far, and I've died A LOT, but I've rarely felt like it was a cheap kill, just my rusty skills.