Web 2.0 is about community
Web 2.0 is about direct communication and community. Social networks are sacred places to some extent. The traditional rules of marketing and advertising don't always necessarily apply. When the commercial web first started taking shape, it was a place very much different than the web we know today. Marketers treated websites as virtual newspapers. Banner ads and in site advertising were thought of in a much more traditional manner. Although websites are still full of advertising and top tier sites and blogs are sustained through ad revenue, the visitors are expecting more than just ads. They're expecting community.
We're not always here to shop
A collection of dot com companies emerged over a decade ago when many predicated that the web would be a big shopping hub. It's true that people spend a lot of money online (look at Amazon), but the web is a much more complex place and suited for more than just commerce. Sure we use the web for activities related to finding information and email, but the web as a whole was severely underrated. It's become a social epicenter and we're just now seeing the tip of the iceberg. Facebook is one the most important places on the web not because it has great functionality or because a programming genius started it. It's important due to the fact that it has become a direct representation of the social nature of human beings. As far as features and usability is concerned, the site isn't even really that much to get excited about. As a true social platform, Facebook still has a long way to go. It's the opportunity that Facebook represents that is truly exciting.
This is the social web. Get used to it
Web 2.0 is becoming more social and it's no longer just suggested that websites and brands take part. It has become an absolute requirement. Users are expecting to connect with like minded individuals online and form stronger connections with those they already know. I want to know what my friends are listening to, what moves they're seeing, what products they're buying, what restaurant's they're eating at, and how it's relevant to my life. Ideas and actions are shareable and can spread like wildfire if they're strong enough and it's what the people want. The Web 2.0 world is so vastly different than the "original" web (I'm talking 1995, 96, 97) that future generations will be astonished at how far we've come in such a short amount of time. It's flat out amazing that anyone in the world can connect with anyone else in the world, regardless of income, age, or culture. The web is open and available to anyone with an internet connection. We tend to take it for granted.