Had the opportunity to attend a seminar on cloud computing in New York last week put on by Amazon, MySQL, Sun Micro, and a local Santa Barbara company called Rightscale.
While much of the seminar is what you would have expected - heavy marketing and cheerleading on the products and services put on by each company, there were some jewels as well. Probably the most interesting discussion was from the enterprise attendees who were either in the implementation/provisioning process, or in due-diligence phase of preparing a cloud processing proposal for their companies.
Security, surprisingly was not the hottest topic (OK, I am humbled, and admit I was wrong on this point). The hottest topic was the cost of migrating applications from the existing IT infrastructure to a cloud infrastructure, and the fact many companies are still using some very old legacy applications that will require major re-writes prior to bringing those applications into a cloud infrastructure.