In a classic disruption described by Christensen and Raynor in Innovator's Solution, Google has moved over the years from offering a software with much less functionality to one that can hit at the core of Microsoft's cash cow operating system. Microsoft's core business is very likely at risk.
This is a very good example of the need for CFO's and corporate planners to start building risk drivers into their driver-based operating budgets. In this case, the volume [# of netbooks sold with the MS operating system installed] is a driver for Microsoft's budgets and the price rate is $15 per installation. While Acer's move was anticipated for some time, with this announcement those revenues are suddenly at risk and should be offset with a risk volume driver [# of netbooks sold that will sold with Google Android instead of an MS OS] to reflect the anticipated reduction in volume.