This year at WinHEC we had a demo that showed the use of ICC and WCS by various applications and system components on Windows Vista.
A part of this was a specially prepared jpeg image with an embedded ICC profile that contains a WCS profile in an 'MS00' tag. The jpeg had its red and blue channels swapped. The ICC profile had its blue and green matrix column contents swapped. And the WCS device model profile had its red an blue primary XYZ values swapped.
The jpeg is a picture of a Ducati "Desmosedeci" MotoGP bike. It is definitely a red motorcycle. So, if you open this jpeg in an application or system component, the apparent color of the motorcycle will tell you how the embedded profile was handled:
At WinHEC, this allowed us to show how applications written to use ICM2 got WCS support "for free" via the WCS-in-ICC mechanism. Besides showing that most of the Office 12 applications (except for Internet Explorer 7) now honor embedded profiles in images, and use WCS for color conversion on Windows Vista, we were able to get Adobe Photoshop to use WCS! If you open the test image in Photoshop (CS1 or 2) on Windows Vista, and tell it to use the embedded profile, you will see a green motorcycle: the embedded ICC profile is being correctly used by Adobe's ACE CMM. Photoshop always uses ACE when converting on-the-fly from the current working space to the display's color space. However, if you do a "Convert to Profile" with "Microsoft ICM" selected as Engine, to most any ICC profile as destination, you will wind up with a red motorcycle: the conversion ran through the WCS CITE transform pipeline and used the embedded WCS profile.
I've attached a zip archive containing the jpeg test image, RGB-Red-Ducati_WCS-Test-TriState.jpg, and an external copy of the embedded WCS-in-ICC test profile, BGR-Wcs-RBG-Icc-Test.icc. See "Attachment(s)" link below. Have fun!