Networks and the Nature of the Firm
Tim O'Reilly

Here is a similar view of the evolution of the enterprise, enabled by the lowering cost of external transactions, the Cloud Enterprise ( which, essentially, is a new type of organisation that uses services provided by partners over the Net. Shared Services just make the offer for services for the enterprise even more granular and agile at the worker level.

Here are a few blog posts that elaborate on the service based enterprise organisation ( of the Cloud Enterprise.

Enterprises today evolve towards the Cloud Enterprise by employing more and more outsourced services and workforce.