And a great post. I would add that Follow > Create > Engage is not always the correct model to use in every situation, although it does work nicely for groups like the Google Lunar X PRIZE, where I work. In fact, our strategy is often Follow > Create > Engage > Convert, where to conversion is the act of creating likeminded cohorts who help with the evangelism. In some circles these people are known as first-tier fans, or tastemakers. They are the die-hards who don’t just care, but help to spread the word.

Just to respond to rquintanilla’s question: absolutely. Twitter works very well as just that, if you’d like. In fact, Twitter has a plethora of uses. Just browse around for a while to see the many ways Twitter is being used (or just flip on CNN sometime).