I am a moral cognitivist. Statements like "ceteris paribus, happiness is a good thing" have truth-values. Such moral statements simply are not compelling or even interesting enough to compute the truth-value of to the vast majority of agents, even those which maximize coherent utility functions using Bayesian belief updating (that is, rational agents) or approximately rational agents.

AFAICT the closest official term for what I am is "analytic descriptivist", though I believe I can offer a better defense of analytic descriptivism than what I've read so far.

EDIT: Looking up moral naturalism shows that Frank Jackson's analytic descriptivism aka moral functionalism is listed as a form of moral naturalism: http://plato.stanford.edu/entries/naturalism-moral/#JacMorFun

Note similarity to "Joy in the Merely Good".