"The actual per-unit pricing is totally uninteresting in my mind," Prashant Ketkar, director of marketing for Windows Azure, told on Tuesday. "What will it cost me end-to-end?"

Ketkar says that Azure offers a number of standard features that, if purchased as add-ons for most competing platforms, cause their prices "to be substantially more expensive than us."

He cited Azure's automated service management as a "killer feature" that enables apps on a downed server to be reloaded onto another server with minimal interruption

Azure is also able to dynamically scale on demand, and automatically create two extra backups of data, Ketkar said.

Iein Valdez, product development director for Appirio Inc., a SaaS systems integrator that supports both Google App Engine and Force.com, disputed Ketkar's cost calculations.