From the Internet:

The color range “xvYCC” is the International standard for wide color space of video applications, and was accepted by the International Electrotechnical Commission (IEC) in October 2005, and will be issued in January 2006. This standard will expand the current color data range by approximately 1.8 times more based on “Munsell Color Cascade”, and it was successfully reached due to the newly developed high resolution signal processing system. Video cameras complying with this standard will be able to record a color variation that is very close to what human eyes can recognize, and TVs complying with this standard will be able to reproduce visual images almost in the same picture quality as it was recorded. In addition, LCD TVs will be able to show the detailed color variation of movie scenes, the different shades of a color, e.g. the red color of a paprika or a tomato, as well as numerous color tones of petal.
I bought a Sony camcorder with xvYCC colour (they brand it x.v.color/x.v.colour). Now when I transfer the HDV to the PC, will WMP play it back with wideband colour? I mean do you need extra software to play it back?