When Oracle announced its intention to acquire Sun Microsystems in April 2009, CEO Larry Ellison proclaimed the acquisition, “transforms the IT industry, combining best-in-class enterprise software and mission-critical computing systems.”

Although he was not ready to use the term at the time, it didn’t take long for Oracle to refer to its combined capabilities as a Cloud Computing solution set, which it recently put on full display at its annual OpenWorld conference.

The event was also a coming out party for its new President, Mark Hurd, the high flying former HP CEO who departed in disgrace only a month earlier. Hurd’s appointment wasn’t hard to understand given his hardware experience at HP and NCR, and now gives Oracle’s move into the system business even more significance.

HP has retaliated by announcing the appointment of Leo Apotheker as its new CEO, along with Ray Lane as its non-executive chairman of the board. Apotheker comes to HP with extensive experience in the software industry, suggesting that the company is ready to counter Oracle’s move by escalating its own efforts in the enterprise software business.

But, Apotheker comes to HP with far less success as a software executive than Hurd achieved in his comparable time in the hardware business. Apotheker resigned as CEO of SAP AG in February after the company had fallen into a deep malaise of slow sales coupled with low customer satisfaction and employee morale.

Despite his dismal record, HP has swapped a successful hardware executive for an unsuccessful software executive.

Like nearly every other industry watcher, my friends at Triple-Tree and I didn’t see this coming when we generated our own list of potential candidates, although we were half-right in suggesting Ray Lane would be a good candidate for the top job at HP, but we didn’t necessarily mean the board chairmanship role.

Apotheker’s appointment is not only aimed at attacking Oracle’s rising threat on the systems side, but is also intended to fend off IBM’s continued push into the software business as well. Big Blue has been on a software buying spree and has done more than HP to position itself in the cloud. CA Technologies has also been acquiring an assortment of young software companies squarely focused on the cloud computing phenomenon. HP also has to reexamine its relationships with Cisco Systems and Microsoft because of their moves into the server and services businesses as well.

HP has also been engaged in an escalating battle with Dell, most recently in its fight-to-the-finish bidding war for 3PAR while it was CEO-less. In addition to competing in the server market, both companies have also deepened their services capabilities by acquiring EDS and Perot Systems respectively. I’ve questioned these moves because they are focused on the old world of IT outsourcing rather than the new world of cloud computing.

But, Apotheker’s appointment also raises serious questions about why senior executives within HP continue to be passed over for the CEO job as outsiders seem to come and go. My guess is that some of these executives will be jumping ship shortly, leaving Apotheker with the additional challenge/opportunity of building a new leadership team.

So, can Apotheker transform HP into a software-driven company? More specifically, can he transform HP’s current software business into a competitive player in the Software-as-a-Service (SaaS) market? And, can he combine HP’s software, hardware and service capabilities to create a viable cloud computing portfolio which can compete on an even broader battlefield?

If the past is any indication, the odds are against him. However, anyone who is familiar with the controversy which surrounded Bill Belichick’s hiring as the New England Patriots’ head coach in 2000 knows that he arrived with plenty of skeptics because he had failed dismally in his only other head coaching experience. Yet, he proved the skeptics wrong by leading the Patriots to three Super Bowl titles in his first five years and has continued to be a contender for the better part of the past five years as well.

Maybe Apotheker can pull off a similar surprise at HP. But, he’ll be facing far greater challenges and failure could have far greater consequences.

Some are already suggesting that one of Apotheker’s first moves should be to acquire SAP, which boasts an attractive installed base of customers who currently rely heavily on IBM systems to power SAP’s enterprise applications. Acquiring SAP would enable HP to square off against Oracle and dislodge IBM from many of these accounts. But, it could also burden HP with an aging set of on-premise applications and the same set of disgruntled customers who were happy to see Apotheker leave SAP before. (I’d be more comfortable seeing HP acquire Symantec, which would fill its security and storage management void, and would fit better into HP’s product portfolio, channel strategy and corporate culture.)

Companies often make bold moves to serve as a catalyst for change. This is certainly the intent of Apotheker’s hiring. However, HP’s board better be sure they found the right guy before they compound their past mistakes by trying to become an enterprise application vendor as well. It wasn’t too long ago that Carly Fiorina was in the midst of a series of highly publicized internal battles trying to prove the logic of her proposed acquisitons of Compaq and PwC.

The Compaq acquisition, in addition to EDS, has made HP the biggest company in the tech sector. But, they haven’t made it a leader in the rapidly evolving Cloud Computing market which is transforming the tech industry.

Apotheker refused to comment about Oracle’s strategies in response to a question during his introductory press conference, but acknowledged that the technology industry is in the midst of a very disruptive transition period as demand for cloud computing services explodes. His ultimate challenge will be transforming HP into a company which can capitalize on this extraordinary opportunity.

Cisco Systems cloud computing Dell HP IBM Microsoft Oracle SaaS SAP AG Software-as-a-Service Sun Microsystems Symantec