We can now do better than "lots", thanks to Kevin.

Someone with some time on their hands could, for instance, tabulate the top-level comments among the 422 posted to "Attention Lurkers".

I've trialed that on a small sample. Out of the 22 first comments, 11 say something that I interpret as "intimidated", 3 say something to the effect that they're no longer interested by the topics on LW, 8 say that they're lurkers but OK with it (or say nothing beyond "hi"). So that's roughly half of them explicitly saying they're intimidated.

The more salient fact to me is that all 22 did write a comment when encouraged to do so and the barrier to participation was suitably lowered.

Another salient comment: "Anytime anyone wants to discuss prenatal diagnosis and the ethical implications, let me know", that being the commenter's area of expertise. We may be missing out on many opportunities to engage, by failing to deliberately open up discussions on topics where the community has hidden expertise.

I'm thinking I will write up a poll-type post asking people what their area of professional expertise is, and which issue in their domain they think would most benefit from application of the techniques discussed on LW.