The indie / intelligent game world is very excited about Braid, Jonathan Blow's new platform puzzle game for Xbox 360 (and soon, PC). Some of the conversation is getting a little overblown, so let me explain simply why Braid is such a fantastic game.
Half the reason Braid is brilliant is the gameplay. It starts off looking like another boring Mario clone. But then you find the ability to rewind time to let you undo mistakes, then you find the bits of the world that are immune to time rewind so you can run causality backwards for everything but the crucial bit to solve the puzzle. Then you keep playing and find more and more complex puzzles requiring time manipulation. It's a fresh game mechanic and the puzzles are very satisfying to solve. I'm usually impatient with games and bust out the walkthrough pretty quick, but the reward vs. difficulty of this game was tuned so well I only used a walkthrough hint for the last piece (and then felt like I cheated myself).
The other half the reason Braid is brilliant is the art. The basic look of the game is watercolour paintings, restful and beautiful. The music is great. The story is compelling and adult, full of ambiguity (beware spoilers) and subtlety. And it's refreshing that the story is told obliquely; as much as I liked Bioshock it's about as subtle as a Hollywood action flick. Braid is more of a David Lynch movie.
The third half of why Braid is brilliant is that the gameplay and the art work together. The time manipulations of the gameplay are direct echoes of the story. The story echoes the gameplay, too, and in fact both story and gameplay are woven together in a complex braid of emotion and ambiguity. There's not many games that have pulled that off, my hat is off to Jonathan Blow.