Megapixels keep increasing

I just happened to be glancing over the ads at Best Buy in the Sunday paper taday and noticed the new cameras are now sporting between 14 to 18 Megapixels. Just curious why anyone would need that much resolution? It's not like there is a huge market out there for amateur espionage or remote sensing, ect. As for myself I am quite well satisfied with my present 8.5 Megapixels as it will easily produce a very clear 20x24 inch enlargement print with no problem at all and can most likely produce even bigger prints although I have no space or frames for such monster sized prints.

Also with cameras in the 14 to 18 Megapixel range, have they increased the size of the image sensor yet? If not, I suspect that hot pixels may become more of a problem at these higher resolutions.

Comments, anyone?