Canon had a purpose in reducing the MP of the G12, it was for noise reduction . The G12's noise is so much better than the 10, its unbelievable. In fact! there are many impeovements over the G10.
I think personaly the G12, will be the last of the really great G series cameras. Their other introductions so far, eliminate some of the G's most attractive features. Not to mention lesser build quality. The 12 feels like a real camera, from what I gather the new ones G15/G1X feel like flimsy digital cameras. Well except!, the G1X is as big as a house.
I assume as you can see the new cameras do not impress me, and I don't care for them.
I've been considering buying a second G12 just to stash back, in case the one I have goes south.
How large of prints bigger than 13x19, mine does that easily, and well.