>>>http://europe.nokia.com/find-products/devices/nokia-808-pureview/specifications
>>>http://betanews.com/2012/02/27/windows-phone-isnt-good-enough-for-41mp-nokia-808-pureview/
>>
>>What would be a practical benefit of having a camera with such high resolution?
>
>No practical benefit. Much higher noise level, lower sensitivity, and far fewer pictures per GB. Most professionals will agree that 10-15 mega pixel gives you best total value.

I tend to agree but it looks like they've reduced the noise problem. Snip:
"The technology means that taking typically sized shots (say, 5 megapixels) the camera can use oversampling to combine up to seven pixels into one 'pure' pixel, eliminating the visual noise found on other mobile phone cameras. On top of that, you can zoom in up to 3X without losing any of the details in your shot -- and there’s no artificially created pixels in your picture, either..."

Also it's a bit like having optical zoom - a small area of the image would still give, say, 5mp resolution.....