Over the last few years, cloud computing and infrastructure—the delivery of business services to users over a network—has taken the IT world by storm. There's hardly an enterprise IT department that hasn't already adopted (or isn't currently considering) a move to cloud-based delivery models, and for good reason: the cloud offers a solution to IT management, resource, and cost challenges facing organizations today. But now that the hype has died down, it's become easier to evaluate how the promise …