Other IT companies that Carr highlights in the book for their innovative approaches to utility computing are: Salesforce.com, which provides CRM software as a service; Amazon, which offers utility computing services called Simple Storage Solution (S3) and Elastic Compute Cloud (EC2) with its excess capacity; Savvis, which is a leader in automating the deployment of IT; and 3Tera, which sells a software program called AppLogic that automates the creation and management of complex corporate systems.

Carr points out that many leading software and hardware companies -- Microsoft, Oracle, SAP, IBM, HP, Sun and EMC -- are adapting their client/server products to the utility age.

"Some of the old-line companies will succeed in making the switch to the new model of computing; others will fail," Carr writes. "But all of them would be wise to study the examples of General Electric and Westinghouse. A hundred years ago, both these companies were making a lot of money selling electricity-production components and systems to individual companies. That business disappeared as big utilities took over electricity supply. But GE and Westinghouse were able to reinvent themselves."

Carr offers a grimmer future for IT professionals. He envisions a utility computing era where "managing an entire corporate computing operation would require just one person sitting at a PC and issuing simple commands over the Internet to a distant utility."

He not only refers to the demise of the PC, which he says will be a museum piece in 20 years, but to the demise of the software programmer, whose time has come to an end.

Carr gives several examples of successful Internet companies including YouTube, Craigslist, Skype and Plenty of Fish that run their operations with minimal IT professionals. YouTube had just 60 employees when it was bought by Google in 2006 for US$1.65 billion. Craigslist has a staff of 22 to run a Web site with billions of pages of content. Internet telephony vendor Skype supports 53 million customers with only 200 employees. Meanwhile, Internet dating site Plenty of Fish is a one-man shop.

"Given the economic advantages of online firms -- advantages that will grow as the maturation of utility computing drives the costs of data processing and communication even lower --traditional firms may have no choice but to refashion their own businesses along similar lines, firing many millions of employees in the process," Carr says.

IT professionals aren't the only ones to suffer demise in Carr's eyes. He saves his most dire predictions for the fate of journalists.

"As user-generated content continues to be commercialized, it seems likely that the largest threat posed by social production won't be to big corporations but to individual professionals -- to the journalists, editors, photographers, researchers, analysts, librarians and other information workers who can be replaced by . . . people not on the payroll."

Carr's argument about the future of utility computing is logical and well written. He offers a solid comparison between the evolution of electrical utilities in the early 1900s and the development of utility computing that's happening today.

Carr's later chapters -- about the future of artificial intelligence and the many downsides of the Internet -- seem less integral to his utility computing argument. And his discussion of Google's vision of a direct link between the brain and the Internet seems far-fetched.

Nonetheless, The Big Switch is a recommended read for any up-and-coming IT professional looking to make a career out of providing computing services to corporations. If Carr's predictions come true, strong technical skills will still be valued by service providers.