At this point though I'm thinking SEO has gotta be dead as a startup business model. It was kind of unknown stuff in 2003 but now the cat's out of the bag. It seems like the last attempt of web 2.0 sites that aren't able to get social adoption is to start flooding the Google index with tag landing page spam or a crappy template page for every restaurant in the country.
I disagree with what Rich wrote about Technorati Tag pages - most people who come to Technorati are coming organically or via blogs, and Tag pages are great way to give your readers a real-time aggregation of all the blog posts, videos, photos, etc out there on a given topic, which is a value to your reader.
But anyway, that's a relatively minor point on an overall excellent post. Go check it out.