Other perks from the iPad competitors: the TouchPad can charge wirelessly with a separate accessory. The Xoom can output HD video.

But the biggest differentiator between the tablets will be their different OSes.

The HP TouchPad will be the first tablet running WebOS, the operating system HP acquired by purchasing Palm last year. The TouchPad will employ the same card stack metaphor for organizing apps found on Palm smartphones. That interface looks even more at home on the larger screen of a tablet. There are few details about changes to the OS for the tablet right now and reviewers got no hands-on time with it.

Android 3.0 ("Honeycomb") on the Motorola Xoom is also new. The OS was specifically designed for tablets, and brings several new interface metaphors, previously unseen on Android smartphones (see an ).

Lastly, iOS on the iPad (due for an upgrade soon) is familiar to anyone who's used an iPhone or iPod touch.