The idea of tagging websites is not new. Some people mentioned that it could help the bigger search engines like Google and Yahoo if a geolocation tag was included in the meta data for webpages. The social bookmarks idea turns it on its head and puts the user/reader rather than the webmaster at the top of the chain. It also is similar to how the Amazon book recommendation system works. I remember Philip Greenspun describing an example of MIT Medialab cluelessness about how some e-jits developed something there called Firefly to suggest potential book choices to customers on a book site while Amazon’s solution was obvious and simple. Social bookmarks system have that elegant simplicity.

Social bookmarks are perhaps more difficult to game than a self-categorisation system because they have a consensus aspect that self-categorisation does not have. Photostreams and their categorisation give search engine operators nightmares.