Usage

The popularity of the term Web 2.0, along with the increasing use of blogs, wikis, and social networking technologies, has led many in academia and business to coin a flurry of 2.0s,[25] including Library 2.0,[26] Social Work 2.0,[27] Enterprise 2.0, PR 2.0,[28] Classroom 2.0, Publishing 2.0, Medicine 2.0, Telco 2.0, Travel 2.0, Government 2.0,[29] and even Porn 2.0.[30]  Many of these 2.0s refer to Web 2.0 technologies as the source of the new version in their respective disciplines and areas. For example, in the Talis white paper "Library 2.0: The Challenge of Disruptive Innovation", Paul Miller argues

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Source:http://en.wikipedia.org/wiki/Web_2.0