That all sounds pretty fair! I don't think I made it clear but I'm fairly sceptical of that particular route myself: I just don't think our conception of "utility" is that coherent. Or to put it in Jasay's terms: I'm not sure we have coherent answers (as a species) to the question of how to weight stuff etc.
I figure morality as a topic is popular enough and important enough and related-to-rationality enough to deserve its own thread.
Questions, comments, rants, links, whatever are all welcome. If you're like me you've probably been aching to share your ten paragraph take on meta-ethics or whatever for about three uncountable eons now. Here's your chance.
I recommend reading Wikipedia's article on meta-ethics before jumping into the fray, if only to get familiar with the standard terminology. The standard terminology is often abused. This makes some people sad. Please don't make those people sad.