IBM has an advantage in its existing massive data centers, which are already equipped to handle customers' needs, Stevens said. What's less clear is whether IBM can convince developers to use its service instead of the popular Amazon Web Services, which claims hundreds of thousands of customers, Bloomberg Businessweek reported last month. "They don't have the pioneering mindshare of Amazon," he said.

IBM has taken steps to remedy that gap. A year ago, it began selling versions of its development tools, middleware, and database software that programmers can access over the Web to build apps. In 2007, IBM and Google started a project to connect universities with computing clouds using open-source software.

More companies are making forays into the market. Hewlett- Packard said last month it would expand its cloud-computing offerings within a year. Microsoft said in October it signed up customers including Toyota Motor Corp., 3M Co. and Lockheed Martin for its cloud software, called Windows Azure.

Eoin Treacy's view Cloud computing bears all the hallmarks of the "next big thing" in the technology sector and related shares are among some of the leaders on the Nasdaq. I last performed a comprehensive review of cloud computing shares on March 4th which may be of interest to subscribers.