Another trend with a healthy stream of innovative games. This trend is also benefiting with the success of downloadable services like XBLA, PSN and WiiWare.
Juan: My pick is Pixeljunk Eden by Q-Games. Much have been said about the game so I won't waste bytes here. One thing that I would say is that no video or description can really explain what this game is about. You have to play it to truly understand it. It's so good it is my favorite game of 2008.
Pixeljunk Eden has a truly unique game mechanic, a very compelling and simple visual style, and contains a whole new challenge in every level by just changing a few simple variables.
Nick: My choice is for this category is Braid, an indie game by Jonathan Blow. It's a borderline casual game, but it's innovation at a mechanic level and its absolutely brilliant level design make it a must-win in my book.
Braid takes the basic platform mechanic of a Super Mario Bros. game and combines it with a few simple and unique twists on time manipulation mechanics. But the thing that moves Braid from interesting to amazing is the strength of the level design. Each mechanic is used to create a handful of extremely tight and well-balanced timing puzzles.
The sheer variety would be impressive, but the genius is the game is the way that skills build from level to level, and that solutions to the puzzles turn out to be just different ways of thinking about the way the game twists time.
Braid is a level design masterpiece, and deserves to be an object of study for any serious game designer.
Other games worth checking out are: