@Charles: even if wildly successful, will not significantly impact Windows in the global marketplace
And the point that I'm trying to make is that MS are missing an opportunity with that approach.
WP7 is going to struggle in the market place, now that MS left it so late in the day to get serious.
Apple have shown that by taking what is essentailly the iPhone OS and adapting it to a tablet device, not only do they satisfy a significant market sector, but they reinforce their iPhone market.
Chrome OS may not kill Windows, but I dare say it will kill WP7, as it almost inevitably merges with Android.