Swords of the Serpentine. I think it's the first game to really combine all the different ideas that have been coming out over the last decade or more (since the end of the D20 glut and the rise of various innovative new concepts). SotS has combined a number of ideas that have appeared elsewhere and made a quite excellent game out of them, and there's going to be a lot of people imitating the style of the game. There are one or two other games which have done some of that, but none seem to me to have done it quite so well.