Microsoft on Wednesday teased a touch-first Office for Windows 8.1, but contrary to many experts' expectations, previewed only one app and declined to define a release window.
During the three-hour keynote address that opened Microsoft's Build developers conference, Kirk Koenigsbauer, the executive who leads the company's Office product group, spent a few minutes demonstrating a touch-based PowerPoint.
Koenigsbauer called what he showed a "preview of our work in progress" that illustrated the "direction we're taking" with the suite's three apps -- Word, Excel and PowerPoint -- implying that they could change dramatically between now and their release.
He did not show either Word or Excel, but did mention the ribbon, the user interface (UI) element that debuted in Office 2007 for Windows and has been a hallmark of the Office applications since, including those that launched last week for Apple's iPad.
"As we built these new apps, as customers moved from Win32 to the Modern [UI], the key is the iconic ribbon," Koenigsbauer said.
He did not hint at a possible release date, not even something general, like "this fall" or "later this year," as Microsoft sometimes does.
That was not what most analysts had expected.
They based their beliefs on comments made by CEO Satya Nadella after the cameras went dark last week at a press event where Microsoft unveiled Office for iPad, an all-touch trio of apps -- again, Word, Excel and PowerPoint -- written specifically for Apple's tablet.
"You'll see us talk even more about [a touch-first Office for Windows] next week, in terms of what innovation we are doing on that platform," Nadella told reporters last week, as reported by Geekwire.
Analysts interpreted Nadella's comments to mean that Microsoft would describe an all-touch Office for Windows 8.1 in significant detail, certainly in more detail than the few minutes that Koenigsbauer spent at Build.
Microsoft may simply be playing its cards close, but the short demonstration, and then only of PowerPoint, and Koenigsbauer's reference to "our work in progress" hinted at a longer timespan before Microsoft ships the "Modern," formerly known as "Metro," apps for Windows 8.1 and presumably also Windows RT, the tablet-specific OS that powers only the Surface 2 and Nokia's Lumia 2520.
The unveiling order of a touch-enabled Office -- first for iPad, Microsoft's tablet rival -- was a major departure from previous company strategy, which has almost universally been "Windows-first" for the company's software. The implied lag between the two makes Microsoft's move of last week to ship Office on the iPad first even more radical.
Whenever a touch-first Office for Windows does ship, it will likely use the same business model as does Office for iPad: reduced functionality -- viewing documents only -- for free, with full functionality available only to customers who subscribe to Office 365.
That's part of Microsoft's plan to drive users toward the software rent-not-own concept, which provides Microsoft with annuity-like revenue and customers with more frequent updates as well as free upgrades.
Just as important is that a touch-first Office, whether on Apple's iPad or a Windows-powered device, is a way for Microsoft to keep customers in the subscription fold once it's managed to herd them there.
"Absolutely, this is about getting people towards Office 365," said Wes Miller, analyst with Directions on Microsoft, in an interview last week. He was referring to Office on iPad, but could just as easily have been talking about a touch-first Office for Windows. "But Microsoft also needs to drive new things to subscribers to help them justify the annuity they're paying," Miller added.
Touch-ready editions, in Miller's opinion, will provide that in spades to some customers. "In business, there are lengthy evaluations before committing to Office 365," said Miller. "But now when the CEO comes and says, 'I need you to get Office on my iPad,' it's a flash point, as is Power BI, that means you should take a look at [Office 365]."
Power BI, for "Business Intelligence," is a set of tools and services that work with Office 365. It launched in February.
The 2-in-1 device form factor that Microsoft and Intel are promoting, however, may require a slight tweak of the Office 365 tie-in model for a touch-first Office on Windows.
Office 365 plans provide rights to install the desktop version, Office 2013, on up to five Windows PCs, including 2-in-1 devices such as Microsoft's own Surface Pro 2, as well as up to five tablets, the iPad touch-only version being the current best example. When Office for Modern -- that last word was widely used Wednesday during the Build keynote, illustrating that Microsoft may have finally settled on it as a label -- debuts, will the device count as one install, even if both are installed, or will the Office 2013 + Office for Modern installs on a single device count as two?
Like most information about the new touch Office for Windows, those answers will have to wait until Microsoft is ready to give them.
Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer, on Google+ or subscribe to Gregg's RSS feed . His email address is email@example.com.