Of all the things Patrick McKenzie has taught me, this one sticks out the most:
There is going to be one far-and-away winner and then there is going to be a massive cliff separating them from second place. Content creation on the Internet typically fits the bill pretty well — winners win, because why would you go to the second best place to get something you need when the first best is, well, better at the same price (free).
This is the basis for the Filthy Linking Rich phenomenon — the page which achieves authoritative status for a particular concept, query, or idea will typically tend to achieve self-reinforcing authority for it.
Winners typically keep winning on the internet. This is a useful mindset to keep-in-mind, and applies to almost every directory on the web: Google search, the iTunes store, Hacker News, Reddit, and even an email inbox. If you’re #1 on those pages, you will get the lions share of the traffic (90% in my experience).
I’m building a course on content marketing right now (for Sept 1st, 2013). You can pre-order it here.