Wow. Here’s a really interesting look as to why advertising, particularly in games, is BAD. It’s actually an argument that I’d never really considered.
In a nutshell: Advertising changes games. It changes the thinking of it’s creators. It changes the experience within the game. It creates visuals that detract from the rest of the game and ultimately doesn’t add to the enjoyment of the game.
Read more here on the Braid web site.