Cloud computing has crossed a Rubicon of sorts, and is now being embraced by a majority of enterprise IT shops - at least according to attendees and vendors at Cloud Expo in New York.

I remember interviewing Hal Stern (late of Sun and Oracle) a couple of years ago at the event, when he said that people were asking him "why should I do cloud?" rather than "what is cloud?" This year, the question is "how should I do cloud?"

There is a mad dash among big vendors, for one thing. IBM and HP have embraced the cloud fully, even to the extent of offering traditional PaaS development services as part of their infrastructure (IaaS) solution. Microsoft has re-launched Azure, in effect, working with new vendors to expand beyong its PaaS roots to become an IaaS vendor designed to compete directly with Amazon. Oracle's Larry Ellison now speaks of cloud as if he invented it, as the database monster now seeks to maintain grip on hundreds of thousands of enterprise IT customers.

Meanwhile, the Battle of the Stacks among Eucalyptus, OpenStack, and Citrix CloudStack is merely part of a larger struggle for market share among the three Open Source companies against VMware, the company that triggered the move toward cloud in the first place.

Cloud Expo had a few highly interesting sub-events within it. In addition to its traditional Cloud Computing Boot Camp and the RightScale conference, this time Cloud Expo hosted a day-long presentation from the Open Data Center Alliance (ODCA), and the initial DeployCon event, which focused on the pack of PaaS vendors who are rubbing against one another for supremacy in this key space.

The word of the day here was "multi-cloud." It turns out that enterprise IT is complex, and that cloud is not going to eliminate that complexity, at least with larger shops. However, it will continue the push in recent years to eliminate silos, decouple and loosely recouple services, get a grip on measuring things, and provide the vaunted "single pane of glass" through which IT management and view and manage what's going on.

Cloud's potential to offer apparently infinite elasticity and to remove some of the day-to-day management headaches when moving things offsite remain as great future opportunities for cloud. But it seems that customers are doing their best to avoid Vendor Lock-in 2.0 and to work with multiple companies to get what they need.

From what I saw at Cloud Expo, the need for highly skilled IT worker bees and managers will only increase as companies realize that they really need to know what they're doing in the cloud; it's not just a buzzterm, not a panacea to IT complexity, but rather, a foundational, transformational change.

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