yes thats the point being made there. Twitter is not really a medium to express any "knowledge" as such. It is basically used to convey short lived information.

yes thats the point being made there. Twitter is not really a medium to express any "knowledge" as such. It is basically used to convey short lived information. The author does not say that twitter aims to be a replacement for blogs, not really. It is a common concern that is expressed at many places that people who blog often might find twitter more attractive.