I expect that was the biggest reason. When I started following OB it basically was Eliezer's blog. Sure, occasionally Robin would post a quote and an interpretation but that was really just 'intermission break' entertainment.

lol, yeah, that's the impression I got in the OB days. When there was discussion about renaming the site, I half-seriously thought it should be called "Eliezer Yudkowsky and the backup squad" :-P

I do note that comments here have been said to have reduced in quality. That is probably true and is somewhat related to lacking a stream of EY posts and also because there aren't many other prominent posters (like Yvain, Roko, Wei, etc.) posting on the more fascinating topics.

Oh man, just you wait! I'm almost done with one. Here's the title and summary:

Title: Morality as Parfitian-filtered Decision Theory? (Alternate title: Morality as Anthropic Acausal Optimization?)

Summary: Situations like the Parfit's Hitchhiker problem select for a certain kind of mind: specifically, one that recognizes that an action can be optimal, in a self-interested sense, even if it can no longer cause any future benefit. A mind that can identify such actions might place them in a different category which enables it to perform them, in defiance of the (futureward) consequentialist concerns that normally need to motivate it. Our evolutionary history has put us through such "Parfitian filters", and the corresponding actions, viewed from the inside, feel like "the right thing to do"; we are unconvinced by arguments that point out the lack of a future benefit -- or our estimates of the magnitude of what future benefits do exist is skewed upward. Therein lies the origin of our moral intuitions, as well as the basis for creating the category "morality" in the first place.