<< That said, I don't think the audience here is indicative of the general internet population. Anandtech Forum people are mostly geeks and/or technojunkies.... so... the resolutions are probably higher (on average) here than the average internet user. >>
Yup, totally true.
I try to make my websites viewable on 800*600 on average. It seems to be the "default" Windows setting and most of your general pc population will leave it as such.
However, just like with anything else that's being published for some mass audience, you need to determine who that audience is. If your making a site for little old ladies to buy yarn from, then definitly consider a lower res. If this is a site for techjunkies, then a higher res will probably work for you just fine.