...actually both are pretty equal in terms of end results. CCD has been more developed over time and is now about equal to the technology of CMOS.
A CCD chip works by having a filter (either red, green, or blue) over it. The image passes through the filter and on to the sensor which then takes that image one pixel at a time and sends a signal to the processor. Hence why 3 chips are better than one, so you can have more vivid colors instead of 1 chip trying to sort out all the colors on its own which doesn't work very well.
A CMOS chip is more heat and energy efficient because it uses less energy on static pixels and its design is very efficient in receiving an image and digitizing the data therefor making it less susceptible to image noise.
Now it may seem that CMOS is a better choice then, but honestly the quality of a CCD chip is now comparable due to the advances in its research.
It's really what the rest of the camera guts can do that I think makes the difference. Type of lens all the way down to the way it records all has an effect on how well those sensors are being used.
......Ok, I'm taking my geek hat off now and putting it next to my pocket protector that's laying on top of my dungeon and dragons player manual...