Megapixels are not at all important today, the megapixel myth comes from the "stone age" of the digital cameras, when the most they had was 2-3. Actually, it's a very real situation, when the high megapixel camera takes worse pictures. What is far more important is the sensor size and the lenses, also the noise control, aberration control, etc. Finally - the ergonomics and the usability of the software. I'm surprised the megapixel number is still such a strong marketing point.. maybe because it's something that all people know by now, even those who never even owned a camera.
I suggest you study some camera reviews here
http://www.dpreview.com/to get an idea what's really important in a modern camera.