http://www.dealextreme.com/details.dx/sku.8673
The details on the keyboard are extremely vague with no real specifications or any information on what the handwriting area is actually meant to be used.
Speculation based on the fact that the handwriting area is described as an identity feature leans toward the touch screen being some sort of security measure. The text area could also be used for inputting Chinese language characters or for simply entering graphic content into the computer.
The good news is that while information on the exact purpose of the keyboard is lacking, the price for the device is relatively low. You can order one online for about $25 at DealExtreme and that price includes shipping. The keyboard measures 16.22-inches x 6.3-inches x 0.51-inches and weighs 28.32 ounces.