IBM is the latest software company to make its wares available as machine images on Amazon Web Services. Expect to see more enterprise-class software vendors do the same as a fast-and-easy way to move their software into the cloud.Just look at the rollout of commercial software on AWS over the past 10 months to see what direction the arrow is pointing. Last May, Sun Microsystems introduced its OpenSolaris operating system and MySQL database on Amazon's EC2. In June, Red Hat followed with its JBoss application server. In September, Oracle reached agreement to offer its 11g database, Fusion middleware, and Enterprise Manager on EC2. In October, Microsoft followed with Windows Server and SQL Server.

When I was at Amazon's Seattle headquarters in November, Adam Selipsky, Amazon's VP of product management and developer relations, made it clear that the strategy was to keep expanding the commercial software choices available to business customers on AWS. "Absolutely," he said. "There are other databases out there. There are a lot of ERP applications. It will be a constant evolution."

So when IBM disclosed that it would begin offering DB2, Informix, WebSphere, and Lotus Web Content Management as pay-by-the-hour Amazon Machine Images, I wasn't surprised. The list of software companies distributing products in Amazon's cloud is sure to keep growing.

Which brings me to a point that I've made before: As AWS becomes a distribution channel for the enterprise software industry, analysts and others (myself among them) are going to want to visibility into that business. IBM, Microsoft, Red Hat, Sun, and Oracle are all licensing software through Amazon, yet Amazon is mum on AWS revenue, growth, and other information that would help us understand how it's going. Pressure will grow on Amazon and its partners to be more forthcoming.