Survey says that 13% are poly and 30% are uncertain or lack a preference. That's higher than the general public.
it might not be much higher once you control for age, gender, location, socioeconomic status, etc.
In particular, I have no idea what fraction of the non-LW-reading but otherwise similar public would say "uncertain/no preference."
This is a thread where people can ask questions that they would ordinarily feel embarrassed for not knowing the answer to. The previous "stupid" questions thread went to over 800 comments in two and a half weeks, so I think it's time for a new one.