Halo 3 is coming, and Wired has a really fascinating article on some of the effort that went into making the game fun for a variety of types of gamers:

Sitting in an office chair and frowning slightly, Randy Pagulayan peers through a one-way mirror. The scene on the other side looks like the game room in a typical suburban house: There's a large flat-panel TV hooked up to an Xbox 360, and a 34-year-old woman is sprawled in a comfy chair, blasting away at huge Sasquatchian aliens. It's June, and the woman is among the luckier geeks on the planet. She's playing Halo 3, the latest sequel to one of the most innovative and beloved videogames of all time, months before its September 25 release.

Most interesting was the description of how the designers took a level where folks were consistently getting lost, and subtly changed the terrain to lead them through in the right direction to get through the level. Anyone who's played (or wandered aimlessly) through the jungle levels outside the library in the original Halo knows this isn't always the easiest thing to get right.

Halo 3: How Microsoft Labs Invented a New Science of Play