Since social web applications are built to encourage communication between people, they typically emphasize some combination of the following social attributes:
- Identity: who are you?
- Reputation: what do people think you stand for?
- Presence: where are you?
- Relationships: who are you connected with? who do you trust?
- Groups: how do you organize your connections?
- Conversations: what do you discuss with others?
- Sharing: what content do you make available for others to interact with?
Social web applications need not exhibit all of these features, but the more attribute areas they cover, the more engaging they are likely to be.
I like this list. It is simple and clean. For every application you design for the social web, you should ask yourself these seven questions.