I just browsed into an interesting article on the knowledge sharing using web 2.0 technology. this article makes for some very good reading.
“What really impresses me about the big Web 2.0 sites is how they use familiar metaphors in new ways. By starting from what we already know (such as profiles, groups, ratings, and ‘friends’), people naturally understand why it might be useful, fun, and easy to add their own online contributions…”
Blog of Intellectual Capital 