I think in this case we have to taboo the term "LWers" ;-). This community has many pieces in it, and two large parts of the original core are "techno-libertarian Overcoming Bias readers with many very non-mainstream beliefs that they claim are much more rational than anyone else's beliefs" and "the SL4 mailing list wearing suits and trying to act professional enough that they might actually accomplish their Shock Level Four dreams."

On the other hand, in the process of the site's growth, it has eventually come to encompass those two demographics plus, to some limited extent, almost everyone who's willing to assent that science, statistical reasoning, and the neuro/cognitive sciences actually really work and should be taken seriously. With special emphasis on statistical reasoning and cognitive sciences.

So the core demographic consists of Very Unusual People, but the periphery demographics, who now make up most of the community, consist of only Mildly Unusual People.