and gain an upper hand over other operating systems, otherwise it will end up behind even Windows in terms of "new", most users want eye candy and extra functionality, they want modern look and design and usability that makes Linux superior to other operating systems, not only technically but visually too. Which is why I like what Canonical is trying to do, good things will come out of it for all, one way or the other, Wayland is the best example, Canonical's development of Mir greatly increased the speed of Wayland development. Even if Mir fails it will still be the factor that brought Wayland to Linux users faster. Competition is good for all.
But I digress, my point was that new ideas, even radical ones like Mir are vital in keeping Linux fresh and modern, competition makes developers think harder and come up with new solutions and design. Thinking in camp terms, us against them is never good because Linux development is intertwined and all benefit directly or indirectly when someone makes something good. I remember how people argued in the past about which desktop environment is better, Gnome or KDE, or rpm vs deb, or Debian vs Suse and the like.