At WordCamp 2009 Matt Cutts gave a 50 page presentation. In it he discussed PageRank, the concept behind it and the importance of avoiding BO (backlink obsession).
As might be expected of a WordCamp presentation he was full of praise for WordPress and suggested the platform takes care of about 80% to 90% of the technical aspect of SEO.
His presentation also contains a slide which recommends the audience "Apply Katamari Philosophy" to their blogging.
But what did he mean by this?
The concept is simply; start with a small niche topic for your blog and then "roll up". Grow that niche once you gain authority in it. It is easier to be relevant and reputable in a niche than in a whole vertical or subject.