The strategy conversation you can only have here
Seth Godin has a very simple strategy for his business of being an author, speaker and publishing the world's #1 marketing blog. As with most great strategies, there is lots underneath it but at the top level it can be explained simply as focusing on 'doing what he does best'.
For his blog he writes short, relevant and opinionated pieces (sometimes more than once a day). They are quick reads and instant gratification to people wanting to keep on top of the world of marketing, which is his specialty.
He is able to do what he recommends all good marketers do, create something that people want to talk about, every day.
On the Incredible Strategies page I've included a a video from outside the TED conference where he talks about his strategies and some of the people who get it right. You'll be interested to hear why he doesn't do Twitter nor Facebook. His reason, he wants to be a meaningful specific rathar than a wondering generality.