Hey Michael,
I'd be a bit surprised if you could find positive, substantive conclusions that metaethicists tend to converge on. My impression is that there's a great deal of disgagreement in the field.
However, I suspect you could find convergence on negative issues--that is, there are certain views, or at least certain combinations of views, that they might all agree should be rejected. Since I don't know metaethics well enough, I won't try to offer an example, but I do know that this happens in other areas of philosophy. To take an example that's already been mentioned in this thread, I think the fact that most people who give serious thought to Popperian Falsificationism converge on the conclusion that it's wrong (even while many people who haven't thought seriously about it find it plausible) is some evidence that they're getting things right.
I wouldn't be surprised if there are substantive theories in metaethics that might seem plausible to people who haven't given them serious thought, but which philosophers have come to reject. If that's the case, then absent foundational worries about their methods, I think we should tend to think that their convergence is evidence that they're right to reject those theories. If we're interested in the questions that Eliezer posted, we should look at what philosophers have had to say about them--even if we're not likely to get the right answer this way, we may be able to eliminate some wrong answers.
My intended next OB post will, in passing, distinguish between moral judgments and factual beliefs. Several times before, this has sparked a debate about the nature of morality. (E.g., Believing in Todd.) Such debates often repeat themselves, reinvent the wheel each time, start all over from previous arguments. To avoid this, I suggest consolidating the debate. Whenever someone feels tempted to start a debate about the nature of morality in the comments thread of another post, the comment should be made to this post, instead, with an appropriate link to the article commented upon. Otherwise it does tend to take over discussions like kudzu. (This isn't the first blog/list where I've seen it happen.)
I'll start the ball rolling with ten points to ponder about the nature of morality...