It's well known in photography circles that megapixels don't really matter. At least, they don't matter nearly as much as many manufacturers say they do (as they race to add more and more pixels to their image sensors). David Pogue at the New York Times
has beaten this drum and now a
new blog Petavoxel takes up the banner.
The long and short of it is that when it comes to megapixels, more isn't necessarily better. In fact, in small point-and-shoot cameras, more megapixels is actually worse. Petavoxel explains:
Most point-and-shoots are based on extremely tiny sensor chips—smaller than your pinky nail, typically. Jamming in more pixels can only be done by making each pixel smaller—thus intercepting less light for a given exposure setting. You can crank up the volume on the fainter signal, but the result is ugly speckles across the image.
Many of last year’s cameras already topped 40 megapixels per square cm; these new ones may hit 50. So we can expect atrocious noise at anything higher than base ISO; or else weird smudgy artifacts from the camera’s desperate noise-reduction processing.
One of the reasons digital SLRs take such great images is that they have large image sensors, allowing the pixels to be larger and thus capture more light. It's probably too much to ask for camera makers to dial back the megapixel war, but you the consumer don't need to fall for it. The amount of pixels on the sensor of the camera is almost literally the least important specification you could concern yourself with.