Sam Harris is here offering a substantial amount of money to anyone who can show a flaw in the philosophy of 'The Moral Landscape' in 1000 word or less, or at least the best attempt.
http://www.samharris.org/blog/item/the-moral-landscape-challenge1
Up to $20,000 is on offer, although that's only if you change his mind. Whilst we know that this is very difficult, note how few people offer large sums of money for the privelage of being disproven.
In case anyone does win, I will remind you that this site is created and maintained by people who work at MIRI and CFAR, which rely on outside donations, and with whom I am not affiliated.
Note: Is this misplaced in Discussion? I imagine that it could be easily overlooked in an open thread by the sorts of people who would be able to use this information well?
I disagree with all your points, but will stick to 4: "Deterrent is nowhere in their brains" is wrong -- read about altruism, game theory, and punishment of defectors, to understand where the desire comes from.
Evolutionarily it is a REASON why the desire evolved that way, but it is not the same thing as what the person FEELS, on a conscious or subconscious level. If you claim that evolutionary reasons are a person's 'true preferences', then it follows that a proper morality should focus on maximising everyone's relative shares of the gene pool at the expense of, say, animals rather than anything else.
EDIT: I'm also curious about your response to all of my arguments.