It was one of those heated hallway discussions: What's the role of the CTO, and how is it different from that of the CIO? And who's at the top of the technology pecking order?

The hallway was in the Westin La Paloma in Tucson, Arizona, and the discussion was between two long-time technology managers. The scene was evening at the InformationWeek 500 Conference, after the awards ceremony. Perhaps a few drinks at dinner had oiled the opinion engines of the two conversants.

Long-time technology manager #1: The CTO is the technology arbiter. It is his or her job to be the person in the organization with the most knowledge of, and experience with, business technology, and to use that knowledge and experience to determine technology strategy and standards. The CIO is a business project manager, pure and simple.

Long-time technology manager #2: That's bull!@#$. The best CIOs are both deep technology thinkers and brilliant business strategists (consider Hewlett-Packard's Randy Mott or Fedex's Rob Carter). It's the CIO's job to vet the CTO's technology strategy to ensure it aligns with the company's business strategy. To be able to do that, the CIO must know more about IT than anybody else in the organization.

Needless to say, no consensus was arrived at. But it wasn't an idle conversation -- well, maybe it was, but the subject matter is not insignificant. The role of the CIO is changing, as more companies look at IT as a set of services to be outsourced or subscribed to, as more business managers understand and exploit for themselves the power of IT to innovate new business opportunities, and as more end users feel empowered to create their own applications through mash-ups and other Web 2.0 technologies.

Is it possible the role (and title) of CIO will disappear and the position (and person) of CTO take over as top technology executive? Or will the CTO role flow into that of the CIO, as technology strategy spreads throughout the organization and the top technology executive becomes a business strategist first and foremost?

I don't know the answers to those questions. I'm just trying to make conversation.