DirectX started out as a rogue operation at Microsoft.  Back in 1995, the future of gaming at Microsoft was something called WinG.  But a group of renegades at Microsoft had a different vision and created DirectX.  Now, at 10, DirectX has evolved into quite a powerful, fully featured, game development environment.

GameDaily Biz has an interview with Chris Donahue at Microsoft over the past and future of DirectX and what it'll mean as Longhorn approaches.