So HN, what sites are we all blocking?
markmail, osdir. these sites basically mirror yahoo/google groups. Big source of frustration.
[I run osdir.com] Just to be clear we're not scraping content nor SEOing to death. We've been running our mailing list archive for almost 8 years.
To quote Matt_Cutts somewhere else in this thread: 'because USENET/mailing lists don't always have a centralized/canonical location on the web, which makes dupe content more of a potential issue. It's not the usual "Website X copied my website" scenario.'
If you dislike us that's cool, but just know we're not showing in your SERPs because of scraping & SEO trickery. A lot of people, maybe not you, really are finding their answer there. There's a lot of solid answers in inboxes.