The tone and rhetoric from the non-believer side has been increasing in its shrillness and hysterics ever since the trolling trio, Dawkins, Harris and Hitchens published their books. Trying to play the victim card, atheists are increasingly referring to Christians as "bigots", God as "evil", and religion as "bad", usually accompanied by a healthy dose of moral indignation, and barely disguised contemptuous outrage.
Not satisfied with only insulting their fellow-evolved, ape-descended, randomly-generated-from-soup-by-thunderbolts-masses-of-hydrogen-and-carbon, non-believers also feel that they should have their own displays representing their secular faith, hence their need to erect their own "holiday" tree.
But do they have an evolved foot to stand on?
All of these acts and insults are born out of a baseless moral outrage. Calling Christians bigots because Christians are "insulting" to atheists is simply stupid if you are an atheist, unless atheists believe that you are insulting pond-scum by calling it, well, pond-scum. Humans may be a step or two above pond-scum on the food-chain (depending on whether you live in California or Texas), but don't protozoans have feelings too? About as much as any other evolved creature, don't you think?
But merely criticizing Christian morality does not establish a tenable moral philosophy for the atheist.
Regardless of which theory of morality/ethics the atheist subscribes, he is still left with a base dilemma of the non-circular definition of morality from a naturalistic perspective. How can a naturalistic derivative decide for or by itself what is ethically normative, if it is naturalistically determined to start with? Whether noncognitivist or cognitivist, ethical naturalism relies on the reduction of ethical terms to scientific or sociological properties, measurable by physiological response. But defining morality based on on human physiological response is question-begging of the highest order. Because it relies on an assumed response for "right" or "wrong" without objectively defining those terms to begin with. How can the ethical naturalist be objective, if he himself is part of the natural?
How one "ought" to respond is not necessarily true for all cases, because morality is normative, or more succinctly, moral properties are normative properties. If an act (or response) has the property of "rightness", then all people ought to act in that way. But the natural properties (pain, pleasure etc), measured as physiological response(s), are not normative, they are simple properties. Also, because not every moral act is reducible to a set corresponding natural property (acts may be right without having the corresponding natural response), ethical naturalism fails. Assuming naturalism as the measure for morality falls on its own preconceptions. Of course, we may be left with the most general argument in favor of humanistic naturalistic morality, the argumentum ad populum or the argumentum ad numerum (majority rules...).
Defining the morally normative remains, therefore, as a basic problem for the naturalist. And their mock outrage stands as a testimony to their ignorance, as much as their "knowledge tree" trumpets it to the world.