They were putting these on some digital cameras for a while and they seem to have fallen by the wayside. They were easily viewable in direct sunlight, unlike any others I have seen. With many, you could turn off the backlight in bright light because the screen used bright ambient light to reflect back through the LCD.
They are still using them for some camcorders, palm devices and even laptops. It seems they would be perfect for the new breed of digital cameras with no viewfinder. And even on cameras with optical finders it is often hard to see to make settings.
There must be a drawback or everyone would be using them. Has anyone heard why transreflective screens aren't common on digital cameras?