The quality of the camera is not based on how many MP the camera has. In really, too much MP can harm the camera if they do not upgrade the sensor of the camera. I am sure you heard the term quantity over quality. It is the same thing here. Not all pixel are created equal. If you jam too many pixel on the same sensor, they tend to have more "noise". Noise is when you take a picture especially in low light and you see all of those red/green/white/ dots all over the place.
So just because you have more MP, it does not mean it will take better pictures. There are other things that determines the quality of the picture like the lens and the processor on the camera.
If in doubt, check out
www.dpreview.com they lots of review on many different cameras.