And there are two other key elements that the Surface still lacks: a ship date and a price. The former isn't too important; no tablet maker has yet threatened the iPad's strong hold on the market, and Microsoft can't really get further behind than "very, very behind" as it already is. The price point, though, is hugely significant. If Microsoft can't compete with the iPad's $499 starter price--let alone the iPad 2's $399 price tag--it's hard to imagine how, barring huge as-yet-unannounced innovations, it could threaten Apple much at all.

Now, if your core business model is making Yet Another Android Tablet that looks like an iPad but is demonstrably inferior, I think you're right to feel a bit nervous that Microsoft is making a play here. And I wouldn't be shocked if the ultrabook market finds that Windows customers prefer the Surface's approach. So even if Apple needn't be worried just yet, I think a few of the competitors it shares with Microsoft ought to be.