At Gartner, much of our coverage of the cloud system infrastructure services market (i.e., Amazon, GoGrid, Joyent, etc.) is an outgrowth of our coverage of the hosting market. Hosting is certainly not the only common use case for cloud, but it is the use case that is driving much of the revenue right now, a high percentage of the providers are hosters, and most of the offerings lean heavily in this direction.

This leads to some interesting phenomenons, like the inquiries where the client begins with, “I’m considering using Amazon, IBM, or Rackspace…” That’s the result of customers thinking about the trade-offs between different types of solutions, not just vendors. Also, ultimately, customers buy solutions to business needs, not technology.

Customers say things like, “I’ve got an e-commerce website that uses the following list of technologies. I get a lot more traffic around Mother’s Day and Christmas. Also, I run marketing campaigns, but I’m never sure how much additional traffic an advertisement will drive to my site.”

If you’re currently soaking in the cloud hype, you might quickly jump on that to say, “A perfect case for cloud!” and it could be, but then you get into other questions. Is maximum cost savings the most important budgetary aspect, or is predictability of the bill more important? When he has traffic spikes, are they gradual, giving him hours (or even days) to build up the necessary capacity, or are they sudden, requiring provisioning in close to real time as possible? Does he understand how to architect the infrastructure (and app!) to scale, or does he need help? Does his application scale horizontally or vertically? Does he want to do capacity planning himself, or does he want someone else to take care of it? (Capacity planning equals budget planning, so it’s rarely an, “eh, because we can scale quickly, it doesn’t matter.”) Does he have a good change management process, or does he want a provider to shepherd that for him? Does he need to be PCI compliant, and if so, how does he plan to achieve that? How much systems management does he want to do himself, and to what degree does he have automation tools, or want to use provider-supplied automation? And so on.

That’s just one of the use cases for cloud compute as a service. Similar sets of questions exist in each of the other use cases where cloud is a possible solution. It’s definitely not as simple as “more efficient utilization of infrastructure equals Win”.