Brilliant analysis of the online ad market from David Koretz at MediaPost:

Apple was able to create a superior user experience with the iPod because it owned the hardware, the OS, the desktop software, and the music store.

As Amazon, Wal-Mart, and others that attempted online music stores can tell you, it is really hard to compete against a piece of an integrated solution.

In display advertising, we have the exact same problem. We cannot compete against search with a piecemeal solution. We need to deliver a deeply integrated solution for intent-driven advertising.