Well, the rumor mill was right: Microsoft CEO Steve Ballmer did show an HP tablet device during this evening's CES keynote. The announcement wasn't quite the Apple-upstaging tour de force some were expecting, though.
Tacked on at the end of Ballmer's presentation, the slate's public appearance lasted barely three minutes. Ballmer actually demonstrated the HP device alongside two other prototypes from Pegatron and Archos, both representing the same new category of devices dubbed "slate PCs." The HP prototype got special attention a little later, as Ballmer showed it running Windows 7, paging through a book in Amazon's Kindle application, and playing back video in Windows Media Player. A short promotional teaser ad was also shown:
The ad doesn't show much, but that pinching motion at the end seems to hint at multi-touch capabilities (as opposed to a more conventional touch screen). Ballmer said nothing of specifications and pricing, adding only that the device will be available later this year. You can see some press renders from HP and a couple of images from the conference in the gallery below.
If we were to hazard a guess about the hardware, we'd say the HP slate PC has a display size around 10" and an Intel Atom processor inside. Windows 7 plus the apparently snappy performance seem to rule out any type of ARM hardware, at least. Those attributes, the bright display, and the thin form factor may also rule out particularly long battery life, however.