The term gets used in a few different ways throughout the Sequences.
IIRC, the post you're referring to is trying to point out some of the contradictions in the way people think about morality, so when it asks "what would you do without morality?" "morality" is used to refer to something other than preferences... something more like objective morality... in order to make the point that even in the absence of that thing, one still has preferences, and that if one's preferences conflict with that thing, one would still prefer to follow one's preferences, so clearly what actually matters is one's preferences.
My summary is perhaps unfair; the whole thing struck me as question-begging, though I happen to agree with the conclusion.
At other places "morality" and related words are used in a broader sense, to refer to an as-yet-unspecified set of values. At still other places "morality" and related words are used more narrowly to refer to the result of some unspecified function that takes as input the preferences of various brains and aggregates that input to generate a coherent set of preferences.
I found it helpful, when trying to make sense of what the author is trying to say in the Metaethics sequence, to keep track explicitly of what "morality" (and related words like "right", especially when italicized) are probably being used to refer to. (In local jargon: Taboo "morality.") He often doesn't use them to refer to what i would ordinarily use them to refer to, so it's easy for me to misunderstand what he's saying.
Today's post, The Moral Void was originally published on 30 June 2008. A summary (taken from the LW wiki):
Discuss the post here (rather than in the comments to the original post).
This post is part of the Rerunning the Sequences series, where we'll be going through Eliezer Yudkowsky's old posts in order so that people who are interested can (re-)read and discuss them. The previous post was What Would You Do Without Morality?, and you can use the sequence_reruns tag or rss feed to follow the rest of the series.
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