I disagree. It is a full vehicle PC.
It runs a heavily customized/specialized version of Linux on an 800mhz Atom processor.
If you read the specs, one of the notes specifically states not to boot the device up w/ a USB memory stick in place because you might not get a system.
That indicates to me that it can likely boot from a USB device, which could theoretically allow you to install Windoze on the unit.
Granted, I think the slower CPU would make a full WinXP install run like a dog, but I believe it's possible.