Ballmer tells analysts that Microsoft’s answer to the iPad is Windows 7 running on tablets (or, in his parlance, slates). On its face, if he means this in the obvious way, their efforts are doomed. The iPad would not be a phenomenon if it ran Mac OS X — and Mac OS X is better-suited than Windows for this sort of thing.

Excellent analysis by John Gruber. Make sure you read the whole article here.

On a related note, Engadget linked to this video today of a touch interfaced running on top of Windows 7.

Truth be told this doesn’t look terrible, but the UI does seem sluggish. More importantly, users are going to have to deal with the typical Windows headaches (Spyware, Viruses, etc). What makes the iPad a great computer is that it doesn’t act like a computer. You treat it exactly like you would a microwave. You press what you want, and out come the results you desire. You don’t have to fiddle with software screaming to get your attention, you just press and go.