One of Microsoft's possible motives behind the XBox:

"Idei [Sony's CEO] saw the PlayStation 2 as a kind of Trojan horse. It looked like a simple video-game device, but it was actually a device that people would use to access the Internet, download movies, watch DVDs, and play music; eventually, it would do everything but curl hair and make toast. The heyday of the P.C. was over, Idei prophesied, and the first contender in the rush to replace it was the PlayStation 2. Soon the headlines were predicting war: 'WILL FUTURE PLAYSTATIONS TARGET PCS?'

With the Xbox, Gates isn't playing offense; he's playing defense.Most of Microsoft's profits come, one way or another, from its domination of the personal computer. Idei, with his talk of replacing the P.C., was effectively marching into Microsoft's house and announcing that he was really going to enjoy living there in a few years. A few months after Idei's Comdex speech, Microsoft announced that it would be developing the Xbox. (A company called Flextronics would handle the production of the consoles.) If such machines were going to become all-purpose, Internet-ready entertainment modules, Microsoft had to get in the game. That meant designing the machine itself; only if it owned the hardware could it control the ground rules, and therefore the software. This is Microsoft's modus operandi. When it decides a new technology is important, it seeks to set the standards, forcing other companies to build to those standards.

The Xbox, then, is a hedge against irrelevance."

(James Surowiecki: The Paranoia Principle. The New Yorker 21.11.2001. This article isn't online anymore, I think)

Other XBox links: [Salon Inside The XBox]
[Salon Dean Takahasi (Excerpt from his book "Opening the Xbox: Inside Microsoft's Plan to Unleash an Entertainment Revolution.")]
Pro: [Salon XBox Ueber Alles]
Contra: [Salon XBox Squared]
[Wired Magazine XBox technology ("There is real power on the pins, notably in a seven-layered slab of silicon code called nv25. This chip is the latest in the flagship GeForce series of GPUs (graphics processing units) made by Nvidia, the Intel of the graphics chip industry. The highly parallel internal design of the newest GeForce means that the nv25 can execute 1 trillion operations per second.")]
[Wired Magazine Making of XBox]
[Wired News XBox Live]