I'm often complaining about the megapixel race. For example I had wished that the Canon 5D mark II had only had 14MP instead of 21, and thus could have had even better low-light performance. And the same goes for recent Canon compacts. But there's a case to be made for the opposite viewpoint.
This article is about DSLRs, but the same principles applies to compact cameras. It seems that higher resolution will compensate for higher noise, so it will even out because the total light gathering area of the sensor is the same. And then you can always downsample the higher resolution image, but you can't invent data from the lower resolution image.
Of course, if you never intend to make prints bigger than, say, 8x10" (20x25cms), then 6MP will do you. But try and find a 6MP camera today.