Well, this article was inevitable - first mentioned here). Francis Heylighen has been talking about this for a few years now as has myself in discussing Hayek, distributed cognition and co-evolved mind and sociality not to mention my ongoing interest in stigmergy which I argue is a species of EM.
Abstract: This article explores the notion of the Web-extended mind, which is the idea that the technological and informational elements of the Web can sometimes serve as part of the mechanistic substrate that realizes human mental states and processes. It is argued that while current forms of the Web may not be particularly suited to the realization of Web-extended minds, new forms of user interaction technology as well as new approaches to information representation do provide promising new opportunities for Web-based forms of cognitive extension. In addition, it is suggested that extended cognitive systems often rely on the emergence of social practices and conventions that shape how a technology is used. Web-extended minds may thus depend on forms of socio-technical co-evolution in which social forces and factors play just as important a role as do the processes of technology design and development.
Keywords: cognition, cognitive extension, cognitive technology, extended mind, Internet, linked data, Web science, World Wide Web.