The M9 is a wonderful device...for some...not so wonderful to others. Like all devices on the market it has strengths and weaknesses. Smartphones are all in one devices that started out as just plain old phones that were used to just make calls. Thankfully that has all changed today.
My point is because smartphones appeal to the masses and not just one type of person, they can be used in a multitude of ways. What a buyer looks for in a device will vary dramatically. Saying someone is dumb for choosing a feature that is important to them because it's not important to you, is ignorance. Same goes for suggesting they should purchase a dslr because they chose a device with a feature more suited for THEM and not YOU.
Purchase any device based on what's important to YOU. It could be the display, camera, phone quality, sound etc. However stop criticizing people for the choices they make based on their personal preference.
Buy the device YOU like, it's YOUR money. If the device fails to meet your expectations then return it or sell it and try something new. If you choose to share your experience, great.
Bottom line, fanboys will be fanboys and haters are gonna hate. They know who they are and so do we.