High Megapixel cameras are completely unnecessary unless you're making poster size prints or doing ridiculously high digital zoom. I'd much rather have a phone with 8MP 2.0?m camera.
this really depends, remember the nokia 41-48mp cameraphone?
if you downscale the images to 8mp they were/may still be the best images you can get out of a phone, however you look at the images at their natural size, you see detail that would otherwise have been lost, it may not be the cleanest detail, but detail none the less, the image i remember was a comparison between the 8mp and 41~48 and looking at the person's shoe, on the 8 you couldn't read the text but on the bigger image you could, though it wasn't pretty.
personally, what i want on a phone is i believe a higher iso so low light isnt so horrible, and a bigger lense/sensor so more light can get focused even if that means bulking out the phone a bit or putting some kind of protector on the lense.