One more thing. Let's define kippt.com as an example. I might bookmark it and tag it as "Web-App-Bookmarking". So after a while if I want to do a comparison on

One more thing. Let's define kippt.com as an example. I might bookmark it and tag it as "Web-App-Bookmarking". So after a while if I want to do a comparison on bookmarking service, I can just pull this tag, I can see a list on every bookmarking service. However, if I just do the keyword search, and that I might already forgot "kippt", I will end up probe so many bookmarking related articles which might contain other stuff. Tagging is just like filtering. It can direct narrow down search list. Tag complexity and various could lead to more accurate contents and its potentially others.