Megapixels is for wimps. Take a look at this!
Seriously - I have been taking macromosaics of butterflies, and when you can zoom into your image right down to the individual scales on the wings - it's absolutely fantastic. You can then of course print these images out (at a fairly large size!) - and the resulting image is extraordinary. Stand some distance away and it looks just like a nice big image of a butterfly. But what's odd - is that you can walk right up to the image, get out a magnifying glass - and see the butterfly in incredible detail (like looking down a microscope).
So if you're interested in this sort of photography pixels (up to Gigapixels) matter.
Nexstar 11 GPS, 2 x Sky 90, M25C, MaximDL, Photshop CS3, Noel Carboni's Photoshop actions, 7 foot Pulsar fibreglass dome, Canon 40D, 100mm macro lens, 28-200mm zoom lens, 17-55mm f#2.8 zoom lens, 100-400mm zoom lens, 1.4x converter, 2x converter.