Investors, says Readerman, must decide what group within cloud computing they will concentrate on. They might, for example, want to focus on "arms merchants," whose products help build clouds by enabling the consolidation of data centers. This group, which has already benefited from the advent of cloud computing, would include companies such as Riverbed (RVBD), 3PAR (PAR), and VMware (VMW).

Investors, says Readerman, must decide what group within cloud computing they will concentrate on. They might, for example, want to focus on "arms merchants," whose products help build clouds by enabling the consolidation of data centers. This group, which has already benefited from the advent of cloud computing, would include companies such as Riverbed (RVBD), 3PAR (PAR), and VMware (VMW).

Because of concerns like those voiced by Hurd (as well as security and effectiveness worries), this shift will occur in stages, emigrating first to what are known as private clouds and then on to public clouds over a period of years. A private cloud usually means the data centers are still owned by the corporate users and managed in-house. But they take advantage of cloud-enabling technologies such as the virtualization provided by VMware and the Internet. (Virtualization software lets one computer take the place of several machines by running more than one operating system -- say both Windows and Linux -- and automatically allocating resources where they're needed to increase efficiency.) If a company uses a "public cloud," this usually means that nearly all of its information-technology operations are outsourced and managed by a third party that owns clusters of data centers.

While Salesforce focuses on a narrow, vertical market with its services, other tech companies like Amazon, AT&T and Terremark World want to become third-party providers of "Infrastructure as a Service," or IaaS. In this case, the user essentially rents out resources that might include data-center space, networking equipment or servers. Thousands of corporate customers, especially new software companies, rely on Amazon's unit, Amazon Web Services, for all or part of their computing functions. Goldman Sachs reportedly outsources a large portion of its IT function to a private cloud managed by AT&T Global Services.

Or they could concentrate on companies that provide partial or complete information-technology infrastructures as a service, such as AT&T (T), Amazon.com (AMZN), Saavis (SVVS) or Terremark World (TMRK), says Readerman.

Or they could concentrate on companies that provide partial or complete information-technology infrastructures as a service, such as AT&T (T), Amazon.com (AMZN), Saavis (SVVS) or Terremark World (TMRK), says Readerman.

Or they could concentrate on companies that provide partial or complete information-technology infrastructures as a service, such as AT&T (T), Amazon.com (AMZN), Saavis (SVVS) or Terremark World (TMRK), says Readerman.

Major tech players like Google (GOOG), Apple (APPL) and Microsoft (MSFT) are all potential beneficiaries -- or possibly losers. They're each expected to enter one or more facets of cloud computing to keep pace with customer demand.