For years, the Google phenomenon has had mostly peripheral impact on enterprise IT as Google chose not to be evil in other places.

For about the same number of years, Microsoft has bumbled around a bit, gliding forward with the unstoppable momentum of a hog on ice but at times appearing to have only equivalent levels of strategy and direction.

But now, with Microsoft inexorably committed to Office Online and Google releasing a revamped version of Google Docs, two of the world's preeminent software companies—and, one could argue, two of the world's preeminent Web companies—are squaring off in what is likely to become an intense, high-stakes, and wide-ranging battle for the hearts, minds, and wallets of enterprise-level CIOs.

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As my colleague Tom Claburn writes in an exclusive news story called With Rewrite, Google Docs Takes Microsoft Office Head On, Google Docs is surging in some corporate environments even when there's been little or no active effort to achieve such an outcome:

At biotech pioneer Genentech, 8,200 people--more than half of all employees--use Google word processing or spreadsheets in a typical week, double the usage from a year ago. "To be honest with you, I didn't know whether people would use this, and there was no mandate or driver to do it," says Genentech CIO Todd Pierce.

Hats off to Google for its guerilla-style efforts at a small but growing number of big accounts where it was able to grab some attention and show its stuff before Microsoft even realized its lunch was being eaten—or, if not eaten, at least pawed through and sniffed at.

But Microsoft appears to have awakened from its multiyear nap and is now retooling itself urgently and aggressively to be a major player in all facets of cloud computing. What that means, I think, is that while Google undeniably won some terrific accounts with fresh ideas and compelling pricing, the competitive dynamics are now entirely different as Microsoft is awake, aware, and hungry for not just parity with Google in cloud-based apps but for dominance.

Again from Claburn's excellent piece: