If you haven't given serious thought to the impact of the cloud, now’s the time. Gartner reports that worldwide revenue from vendors selling external disk storage subsystems for cloud-based systems will grow from $267.4 million this year to $1.45 billion in 2015. Additionally, companies selling private and/or public cloud storage have seen annual revenue grow some 56 percent to date this year compared to 2010. Note the distinction being made here. These numbers reflect spending on external controller-based clouds -- any public, private or hybrid cloud that serves multiple customers. Internal clouds that exist behind corporate walls for use by a single firm aren’t counted. So far, these external clouds represent just 1.4 percent of the overall external array-based disk storage subsystem revenue from last year, so this is an early stage market. Software as a service and infrastructure as a service providers will lead the upcoming growth, Gartner says. The real message here is pretty simple: Even though we’re already suffering through an overload of cloud hype, it’s just getting started. The numbers show that migration of mission-critical business tasks to the cloud in organizations of all sizes is going full steam ahead. Are you coming along for the ride? You can find the entire Gartner report here.