Just because I agree with his take on religion, is not an agreement in toto.
Utilitarianism:
Utilitarianism is the idea that the moral worth of an action is determined solely by its contribution to overall utility: that is, its contribution to happiness or pleasure as summed among all people. It is thus a form of consequentialism, meaning that the moral worth of an action is determined by its outcome. Utility, the good to be maximized, has been defined by various thinkers as happiness or pleasure (versus suffering or pain), although preference utilitarians like Peter Singer define it as the satisfaction of preferences. It may be described as a life stance, with happiness or pleasure being of ultimate importance.
Utilitarianism is described by the phrase "the greatest good for the greatest number of people". Therefore, it is also known as "the greatest happiness principle". Utilitarianism can thus be characterised as a quantitative and reductionist approach to ethics. It can be contrasted with deontological ethics (which do not regard the consequences of an act as the sole determinant of its moral worth) and virtue ethics (which focuses on character), as well as with other varieties of consequentialism. Adherents of these opposing views have extensively criticised the utilitarian view, but utilitarians have been similarly critical of other schools of thought. And like any ethical theory, the application of utilitarianism is heavily dependent on the moral agent’s full range of wisdom, experience, social skills, and life skills.
Easily dissected, I cannot agree. As human beings (both on an individual basis as well as collective) have proven multitudinous times, the strong swim towards pleasure can often lead towards disastrous results. The sexual revolution, for instance, came about because of the ability to treat STDs like gonorrhea and syphilis with the pop of a pill (there are other reasons of course, but I consider that a primary). Decades later, penicillin-resistant strains of these poxes bedevil us still.
Singer is the foremost proponent of animal liberation:
In Animal Liberation, Singer argues against what he calls speciesism: discrimination on the grounds that a being belongs to a certain species. He holds the interests of all beings capable of suffering to be worthy of equal consideration, and that giving lesser consideration to beings based on their having wings or fur is no more justified than discrimination based on skin color. He argues that animals should have rights based on their ability to feel pain more than their intelligence. In particular, he argues that while animals show lower intelligence than the average human, many severely retarded humans show equally diminished, if not lower, mental capacity, and intelligence therefore does not provide a basis for providing nonhuman animals any less consideration than such retarded humans. He also points out that many primates have learned to communicate with American sign language (ASL) or symbol languages. These include chimpanzees, gorillas, bonobos and an orangutan. Primates that have learned ASL or symbol languages include Washoe, Koko, Chantek, and Kanzi. Likewise, pigs, birds, primates and cetaceans can rank as being as intelligent as children. Singer does not specifically contend that we ought not use animals for food insofar as they are raised and killed in a way that actively avoids the inflicting of pain, but as such farms are uncommon, he concludes that the most practical solution is to adopt a vegetarian or vegan diet. Singer also condemns vivisection except where the benefit (in terms of improved medical treatment, etc.) outweighs the harm done to the animals used.
I am foursquare and unapologetically a speciesist. Because of the commonality of biology I share with my fellow human beings, I will likely rate them higher on the value scale (there would be exceptions: people who would prey upon animals for the mere enjoyment may incite me to some level of anger, and devalue themselves). So I would still value a human being (mentally challenged) higher than a primate. I am not in favor of animal suffering: I see that as irrational.
Abortion:
Singer states that arguments for or against abortion should be based on utilitarian calculation which weighs the preferences of a mother against the preferences of the fetus. A preference is anything sought to be obtained or avoided; all forms of benefit or harm caused to a being correspond directly with the satisfaction or frustration of one or more of its preferences. Since a capacity to experience suffering or satisfaction is a prerequisite to having any preferences at all, and a fetus, at least up to around eighteen weeks, says Singer, has no capacity to suffer or feel satisfaction, it is not possible for such a fetus to hold any preferences at all. In a utilitarian calculation, there is nothing to weigh against a mother’s preferences to have an abortion, therefore abortion is morally permissible.
Similar to his argument for abortion, Singer argues that newborns similarly lack the essential characteristics of personhood — "rationality, autonomy, and self-consciousness" — and therefore "killing a newborn baby is never equivalent to killing a person, that is, a being who wants to go on living."
I would go along with the first paragraph, but no to the second – again, my speciesist tendencies revolt. This is an evolutionary mechanism built into us. It is not the only yardstick. There is the potential future folded into the infant – it is a (non-supernatural) wonder waiting to blossom, a flowering of a new being…I could go on some rhetorical flourish, but the short version is I’d likely give my life to save a baby. Hard to argue with that, I think.
I have no argument with his stand on poverty – it’s sensible.
Zoophilia – now I have an issue.
In a 2001 review of Midas Dekkers’s Dearest Pet: On Bestiality,[35] Singer stated that "mutually satisfying activities" of a sexual nature may sometimes occur between humans and animals and that writer Otto Soyka would condone such activities. Singer explains Dekker’s belief that zoophilia should remain illegal if it involves what he sees as "cruelty", but otherwise is no cause for shock or horror. However, Singer does not claim to endorse the views of either Dekker or Soyka, merely to be explaining them. Singer believes that although sex between species is not normal or natural, it does not constitute a transgression of our status as human beings, because human beings are animals or, more specifically, "we are great apes". Some religious individuals and animal rights groups have condemned this view.
This is a major problem – where one can indeed be too liberal. It may not ‘constitute a transgression of our status as human beings’, but regardless of the fact that we are animals, bestiality is rated as a mental disorder, and for good reason. An inability to form a sexual liaison with another adult, a frisson for something that’s not human, is decidedly abnormal. I am not committing the naturalistic fallacy when I state that animals are incapable of granting consent – so are children, because when it comes to human beings, either you can communicate, or you can’t. Silence as assent was bogus when Plato said as much, and it still is. And really, how many dumb animals can actually say no?
I would go as far to say – that the application of bioethics vis-a-vis utilitarianism lends itself to a breakdown of moral universalism (of which I’m a proponent). Consider:
It is widely considered that infants are a high value to any society at large, regardless of level (we shall grant this a high degree of universality, shall we?). It’s a survival mechanism to breed in numbers. By applying the above principles (i.e., giving animals a higher value rating than infants, despite the ability of the latter to develop cognition incrementally), we lose fundamental values we normally ascribe to potential moral agents. One might argue that the word ‘potential’ is meaningless, but we live in a society (and indeed a world) that is built on the concept of potentiality. Potentiality has value. “The children are our future!”, while somewhat trite and cliché, still stands.
The slippery slope is not my favorite specter to invoke - I see it abused gratuitously on the internet. But there is merit in it sometimes. If we change the moral value of an infant in society’s eyes, it stands to reason the infant will become more abused. If we grant the non-human animal greater status than we grant our own children (a sentence that I personally never dreamed I would write or speak), then it is my opinion that we lose – both in the short term as well as the long term.
As to the zoophilia angles – well, I’m sorry, but there is such a thing as being TOO liberal. With the rising tide of pandemics (from the Avian flu to the Swine flu), this option is anything but viable.
Is it really any surprise? 
I read this over at 
Dobson/Robertson/Warren, et.al., get face-time with President Obama, why didn’t the SCA?
forward to a respite from xian gobbledy-gook and dog-whistle code. It seems my hopes are dashed.
