So we've all read the information out there about on page optimization using title tags, h1 tags, bold text, keyword density, etc. and we all know about the importance of inbound linking. What about more advanced SEO techniques? What is it out there that the big boys are doing that isn't common knowledge? I've noticed a few sites that have picked up dmoz listings and redirect them to there sites. I've seen large product databases cross linked accross multiple sites. I've come accross the notion of astroturf advertising once or twice. (Paying people to post good things about your sites around the internet). There's also PRWeb, PRLeap, PRNewswire, etc. which are all pretty decent. Using subdomains seems to be a popular idea but I don't actually see very many subdomains in the SERPs that I see on a daily basis. And then there's having a large network of sites based in different locations, and large sites themselves. What am I missing here. I'd really like to compile a list of various strategies, and maybe links to where people(i.e. me) can get more information about the strategies. Even the expensive and elaborate ones.
I don't follow seo's too much, but recognize patterns within the search engines. My advice would be to not pay too much attention to well meant advice (often generic), but rather strenghten your domains with content, links and continued advertising (such as in directories, thru blogging and creating stuff that others link to voluntarily)
I would say advanced seo techniques can often be figuring out how to do more of the same cheaper or virally.