Clay Shirky: Hailstorm: Open Web Services Controlled by Microsoft. In decentralizing their control over the client, Microsoft seeks to gain control over a much larger set of functions, for a much larger group of devices, than they have now. The functions that HailStorm centralizes are in many ways more significant than the functions it decentralizes.
See also: Soap InterOpera, from XML Magazine (edited by my brother, Steve).