Microsoft has joined the billion dollar club. For Azure, that is. They announced that this platform and service will generate a billion dollars in revenue. It's been growing, and at least one analyst expects the revenue to double annually. Profit is something else, but I know from various people at Microsoft that they are working hard and investing heavily in this service, and I'm sure at some point it will be profitable, though I'm not sure how much.
Amazon has had a very successful AWS platform, providing a wide variety of services and products. Their aim is to go for the high volume, low margin business, which makes their service competitive with the costs of buying and managing your own hardware. As long as Amazon and other competitors are out there, I suspect cloud services will be cheap enough to make many companies consider moving some of their infrastructure to this type of environment. It certainly eases the time and effort of building new machines and encourages better development habits.
As IT departments, especially the management of those groups consider using cloud type services, they still have to be aware that this isn't a savings that comes for free. Code changes, staffing skill growth and mindset evolutions to take into the account the challenges of working in a cloud environment, as well as the SLAs that seem to favor the cloud providers more than the cloud customers, mean this isn't an easy decision. Add to this the potential tax implications, and the decision to move away from current IT practices is not always obvious.
The idea of cloud computing, and cloud services, is still very immature. From the definition of what this means, to the offerings, to the architectures, the industry has a lot of growth to do before most of us will feel comfortable moving substantial parts of our infrastructure out of our own facilities.