It's one of the main schools of ethics, with a pedigree that goes back to the Greeks. This seems to be a reasonable summary.
Note that the article mentions Dennett's criticism of utilitarianism (one major criticism has always been the impossibility of utilitarianism's moral calculus); some people on this site would try to lump Dennett in with Singer, but in fact they're philosophically diametrical opposites - unless, of course, your world is divided into the Godly and heathen atheists.
All schools of ethics are acceptable???? Why should something that leads to acceptance of infanticide be tolerated? Shouldn't there be limits to academic freedom?