I’m here at the Software 2007 conference in Santa Clara, Calif., attended by a who’s who of Silicon Valley CEOs and other executive managers, all talking about what’s next in software innovation.

I saw many of them at an invite-only lunch that wrapped up a few hours ago, but I spent most of my time listening to what FedEx CIO Rob Carter, seated at my table, had to say about what’s happening in the world of software. (In the CIO world, Carter is as close to celebrity as they come.) I have to listen to software vendor celebrities for the next few days, guys like Steve Ballmer and Marc Benioff, and I needed a reality check. I knew Carter would speak on a level of truth I’m not as likely to get from a software exec’s marketing-conscious rhetoric.

Here’s what Rob Carter had to say on…

Software as a service: Carter is not sold on on-demand software for FedEx, also known as SaaS, despite the fact that SaaS adoption is growing and considered among the most obvious examples of innovation. The SaaS poster child, Salesforce.com CEO Benioff, has approached Carter “many times” about Salesforce’s SaaS offerings, Carter said. But FedEx already has onsite customer service and sales force automation software that work great. FedEx is an acquisitive company, Carter noted, and SaaS is more likely to make sense for, say, FedEx subsidiaries. After lunch I spent some time talking to Benioff, who noted that FedEx subsidiary Kinko’s is, indeed, a customer of Salesforce. Still, Carter confirmed what many of us already suspect: Many big companies aren’t yet impressed with SaaS to the point they’ll consider replacing what they have, if what they have works just fine.

Windows Vista: Carter’s security team loves the new security features in Vista. FedEx’s chief security officer, in fact, is responsible for the rollout of Vista on company computers. It was a little unclear to me, though, exactly when FedEx plans to roll out Vista, and to what types of users.

On IT budgets: Software 2007 conference organizers keep talking about the rebirth of innovation in Silicon Valley this first day of the show, but based on what Carter said, it doesn’t sound like IT budgets quite match that level of enthusiasm. CIOs aren’t necessarily holding back on IT spending this year, but there are plenty of business pressures that continue to keep IT spending in check, he noted. Auto and jet fuel costs are a big one, for example … and things that directly impact FedEx, of course. Are IT budgets improved over the early 2000s? Yes. Will IT spending return to the frenzy of the late 1990s? Not a chance.