Many applications running today require access to the NTFS APIs in Windows. A major requirement of getting these applications to run in the cloud is to not break the application dependencies on these NTFS APIs. For this reason, Microsoft is building something called the Windows Azure Drive which is currently in beta.
You can find a more comprehensive look in this Windows Azure whitepaper.
This will allow businesses to gain the advantages of the cloud while leveraging existing software investments. This could be a niche for cloud computing that a lot of small IT shops could profit from, by proposing and implementing this for clients, all the while saving clients money by decreased server administration costs and increasing availability of applications. As usually, there will also be the need for IT experts in dealing with the risks of who owns and controls data stored in the cloud, what exit strategies are planned for in the case cloud computing does not work out, and other risks so that customers can explore new opportunities while protecting themselves.