Despite the excitement, however, many independent software vendors are unsure of what SaaS will mean to their businesses, their customers and their potential to make money.

Many ISVs brought those questions with them to the "Software Business Transformation Summit: SaaS, Subscription Models and Open Source Take Hold" conference, held Tuesday and Wednesday this week at the Mirage hotel in Las Vegas and organized by technology analyst group The 451 Group (the451group.com) and its research subsidiary Tier 1 Research (tier1research.com).

According to Andy Schroepfer, founder of Tier 1 Research and one of the event's key organizers and speakers, a significant majority of the 200-or-so attendees are ISVs looking for a little clarity on how they can deliver their applications using the SaaS model, and how they might expect that to affect their businesses financially.

Unlike many of the events in which Web hosts circulate, the SaaS Summit is notably less focused on meeting and networking than it is on sitting down and observing and participating in the two days of steady sessions. Certainly, there is time set aside for networking, and there is networking being done, but there is a demonstrable sort of scholastic commitment to the material being presented.

More than anything else, the event relies on the capacity of 451 group and Tier 1 to educate. Fortunately, that ability is considerable. The sessions themselves are laid out in a progression that follows a lesson-plan sort of logic, building from a basic understanding of the SaaS concept to pinpointing the roles of open source, licensing models, infrastructure and consolidation.

Schroepfer says the message of the event is that SaaS is happening. The revolution, such as it is, is already happening. But there is still a long way to go.

He began the speaking program by evangelizing the concept itself. He's convinced that the model is the future of, not software delivery, but service delivery. The concept's value is partly that it recognizes that customers don't value technology, but service. And the SaaS model makes technology irrelevant, delivering service and functionality in a manner that removes software-related concerns like deployment and upgrades from the customer's experience completely.

Following Schroepfer's introduction was a presentation by Phil Robinson of SalesForce.com (salesforce.com), a company that presenters throughout the event describe as the "SaaS poster child." Salesforce, says Robinson, began its business with the model now being described as SaaS. As the company's product evolved, and concepts of software delivery evolved around it, Salesforce.com built its product into an application development and delivery platform called AppExchange, giving software developers a means to build and deliver applications, as well as a built-in audience.

Both of the first two presenters regularly referenced Google, a company that, while somewhat of an anomaly by software development standards, is helping to set the standard for delivering functionality through the SaaS model, and providing inspiration to the SaaS believers.

From the initial evangelizing, the sessions moved into more specific detail during a series of panel discussions - choosing the right software model, the changing nature of software licensing and the new direction for application infrastructure.

Throughout the panel discussions, it was the conflicting opinions, in part, that painted a picture of SaaS as a work in progress conceptually. But the commitment of everybody involved showed a model that already has the support and ambitions of the software business behind it.

The feeling of unity arose as presenters, on message, repeated the key mantra of delivering function as opposed to delivering software.

The conference continues on Wednesday, with a focus on open source in the enterprise and development for Web 2.0.