I believe that the IT field is going down the same path with virtualization as it does with many disruptive technologies. We tend to implement first and ask questions later. For example, when the PC started to become very popular with businesses, big-iron mainframes started to become obsolete and companies' PC ownership grew exponentially. The buzzword of the day was "distributed computing." Now we have huge fleets of PCs that are often difficult to manage and are riddled with security problems.
The IT field is looking at this now and saying, "Hey, we might have a problem. Maybe leaving the computing power in the data center was not such a bad idea after all." The problem is that users have become accustomed to the flexibility that distributed PCs offer. In comes virtualization to solve some of these management and security problems on both the desktop and server side. So we implement, implement and implement this new technology that is the savior of the day. As virtualization technology like VMware becomes more of a commodity, its implementation will grow exponentially -- just like the rise of the desktop in the corporate environment. We are just now looking at this situation (in my opinion, much faster than we took notice of the desktop situation) and trying to decide if there are inherent problems in the virtualization platform.
As it turns out, security in a virtual world may be an issue. We are now asking questions like, "How do I control virtual machine patching when snapshots and rollbacks can be performed routinely?"; "How do I secure my virtual machines if the network they use to communicate with one another is inside the physical server?"; and "How do I detect and prevent rogue virtual machines from showing up on my network?" The company that is able to answer these questions with proven solutions should be successful as virtualization technology becomes a commodity.
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