Yesterday I wrote a post about the need for CIOs to deliver business value, citing a Constellation Research report that listed the four personas CIOs will need to master if they hope to be successful. In Constellation's opinion, the personas are: chief infrastructure officer, chief integration officer, chief intelligence officer and chief innovation officer.

Of course, this kind of debate over CIO roles and responsibilities is nothing new. In 2009 I wrote about shifts in CIO responsibility, noting that attendees of a CIO event suggested their title could just as easily be chief simplicity officer, chief organizational officer or strategy execution officer.

In 2007 I called the CIO the most thankless job in the enterprise, sharing author and provocateur Nicholas Carr's opinion that the CIO is the least defined position in the C-suite and also "the most prone to identity crises."

In 2006 I said the CIO was the James Brown of the enterprise (because he or she is so hard working), citing an EDS fellow's opinion that CIOs must fill at least seven roles in addition to chief information officer: chief investigative officer, chief international officer, chief inoculation officer, chief identity officer, chief innovation officer, chief integration officer and, our favorite, chief irritation officer. (Obviously, there's some duplication between this list and Constellation's.)

I was delighted to stumble upon a Twitter conversation between between a couple of folks regarding my post that mentioned the Constellation Research personas. Andi Mann, a VP with CA Technologies, tweeted my post and asked:

What's the "I" in CIO? Information? Infrastructure? Integration? Intelligence? Innovation? The lot?

Ian Massingham, a CTO for Service Providers across the EMEA region at EMC, responded, "soon it'll stand for cloud interface officer." I think Massingham is on to something. A cloud interface officer sounds a bit like the cloud broker role IT Business Edge contributor Mike Vizard wrote about last week.

No one doubts the future importance of the cloud, but I "borrowed" Massingham's suggestion and made it a little broader. I like the idea of a chief interface officer, who could serve as a needed interface between IT and the broader business.

(Yes, I know that folks who say IT should already be a key part of the business might not think an interface is needed at all. But unfortunately there's still a pretty big gap between IT and business at many companies.)

One of the things I found most interesting about the four Constellation Research personas, based on a CIO.com article about them, was Constellation CEO Ray Wang's take on them. The persona companies care less about all the time, chief infrastructure officer, is the one that still commands the lion's share of the budget, 65 percent to 70 percent, according to Wang.

In contrast, the chief integration officer manages 5 percent to 10 percent of the budget, while the chief intelligence officer gets 10 percent to 15 percent of the budget and the chief innovation officer gets 5 percent to 10 percent.

Even as the other three personas grow in importance, the infrastructure persona will remain relevant. That's because tight IT budgets will require CIOs to optimize existing investments (the bailiwick of the chief infrastructure persona) to fund new initiatives identified by the chief innovation officer.