"The stock Sony camera app just applies some "magic trick" - aka software library - to do some filtering and noise reduction. Maybe because of patents, that library would only work if fed with some DRM-like key. else it would just resize down to 8Mp, actually castrating the camera. This is why we should talk about that noise reduction and low light thing instead of Le Twenty Mega Pixels meme."

That's what the meaning behind "Sony 20MP camera" and other goodies like its display from Sony's proprietary features (Song "magic trick") locked by DRM key. It's not purely 20MP vs 8MP by the figures.