Ummm no? Pixel density is the amount of photoreceptors on a chip divided by the surface area of the chip (high mp count on a small sensor, like a smartphone's, for instance, means high density) .Because higher pixel density means less dynamic range and baaaaaaad high iso performance, both of which poke you in the eye when you even glance cursorily through a photo. That's why the best (and most expensive) cameras have humongous sensors, and that's why the low light photos from professional cameras look amazing.

Higer MP, on the other hand, need to be printed on ginormous sizes to make any difference. To be honest, I think that 8mp is about 2 too many on a phone. I have printed some amazing shots on A3 paper from my 5 megapixel Olympus E-1, with a manual focus lens. The quality of the sensor, the lens and, lets not kid ourselves, the skill of the photographer, is far more important than the sheer amount of pixels.