As with all things "cloud" these days, there's an interesting dichotomy between those who are head over heels excited about the huge potential of private cloud approaches and those who see it as a marketing-driven rebrand of what everyone is already doing: virtualizing the data center. In the end, the truth is somewhere in between.
Although the private cloud has the potential to solve many of the scalability and service-delivery challenges that larger IT departments wrestle with, it is not magic. Really reaping the benefits of the private cloud requires an IT-savvy customer base, a willingness from the executive suite to adopt a chargeback model, and no small amount of work to configure it in such a way that it will actually save everyone time in the end.
At the same time, a true private cloud implementation is not just data-center virtualization with a new coat of paint. Although it's true that much of the gear you might use in a private cloud ends up being put together in the same way as you would in a traditional virtualization model, the self-service nature of the private cloud demands a completely different mindset from those planning and building the underlying virtualization and storage infrastructures.