First 3 Generation-Compatible HD DVD Drive
fenimor writes "NEC has developed world's first half height size optical drive capable of playing back HD DVDs, DVDs, and CDs with a single optical head. Although the lasers required to read each type of disk vary, NEC said it had successfully created a miniature drive with a single lens that could read all three. The drive was designed for laptop computers and will be released commercially later next year."
Firstly, this is just a press release and the announced arrival is very similar to the announced arrival of blu ray devices in the North American market.
Furthermore, blu ray devices are available right now in Japan, and have been for a bit.
I think it is a different case because the size of media and media type wasn't remotely compatible back then.
While existing CD players probably won't die quickly, DVD and CD compatibility for a next generation format was known to be a must by pretty much all manufacturers. I think previous system prototypes used multiple optical assemblies to achieve the desired compatibility.
The market is highly steeped toward backward compatibility now, systems that aren't backward compatible don't have a chance.