I noticed this on my laptop also. Switching to a couple of old games i put on the computer and opening the games brought the "changing color scheme" message. The laptop has now switched the vista to the basic color scheme all the time.
From paul therrots website
Windows Vista continues with XP style themes, though it only offers two types, Windows Vista and Windows Classic. More interesting is the new Color Scheme applet, which lets you dramatically alter the look and feel of the Aero user interface and should answer any complaints. Microsoft supplies a number of stock Aero color schemes, such as Aero (the default), Frost, Smoke, Seafoam, and others, which colorize the Aero window chrome in various ways. But you can also use this applet to disable the Aero transparent glass effects (essentially giving you the now-missing Aero Express look and feel) or vary the intensity of those effects using a sliding scale. Finally, you can use an advanced color mixer to really fine tune the look and feel of Aero via different color, saturation, and brightness controls.http://www.winsupersite.com/reviews/winvista_5270.asp
The glass effect is what goes out when you run a program that cannot handle the applet. It is too bad that microsoft decided to not make it backward compatible with XP systems.