Neil, you're mixing up market share with usage data.

Particularly in the case of the browser, no one buys one so there really is no "market."

Particularly in the case of operating software, Net Apps only measures the O/S of desktops and other devices using the web to access NetApps customers. You're right that measuring such things is tricky but NetApps way is beyond tricky--it's not meaningful.

Further, the desktop software you mention is only a small part of Microsoft's total. I'm not saying Microsoft won't lay anyone off but it won't be for the reasons mentioned here. Maybe Microsoft's share of the software market will drop from 25% to 24% in 2009 too but it won't be because of Google apps.

P.S. My gotcha last line was going to be "a 750-pound gorilla is still hard to stop." But I alwyas screw up the punch line.