Very nice summary of strategies from Smashing Magazine. One of my favorite related strategies is: scale interfaces for users. It helps both first time users determine how much complexity they want and need to get their task done, as well as returning users who have increased in skill using your application.
This is a strategy we try to employ everyday at Addthis. Many publishers just want to grab AddThis code and go, so we built a simple process to do so right up front on the home page, no registration required. Huge enhancement to user experience for our visitors, and enormous uptake for overall usage of AddThis. Want more options? Sure, no problem! But publishers don't have to deal with complexity if they don't want to.