XBox Live Network
The New York Times covers Microsoft's planned XBox Live network, a subscription-based online service for the XBox. Microsoft's "we control everything" approach will probably impact the number of games available, but the article notes that the service will include voice-over-ip, which might be a selling point.
When MS inundates the market when the lower the price to $99 of the X-Box, they certainly will have a better opportunity for another monopoly.