FORTUNE -- Two and a half billion dollars.
Here how he gets that number.
For starters he estimates that Microsoft probably sold fewer than 1 million Windows-based tablets last year and will be hard pressed to capture 10% of the tablet market this year -- especially with stalwart partners like Hewlett-Packard (HPQ) reportedly choosing Android over Windows 8 for its forthcoming mobile devices.
He also reports that three to four times as many Mac users (30-40%) install paid versions of Office on their machines as Windows PC users (10-15%) do -- a difference that feels too high unless he's not counting the discounted versions of Office Home edition that come bundled with new PCs.
Assuming a similar 30% attach rate in 2014 on roughly 200 million iPads at an average selling price of $60 comes to more than $2.5 billion in extra revenue per year, even after Apple takes its 30% cut off the top.
That's more than Holt forecasts Microsoft will make from selling software (Windows and Office) on all Windows-based tablets in 2014.
"The math is compelling," he concludes, "and may drive MSFT to move Office."
Apple iPhones and -- surprise -- Windows tablets, according to a new Forrester survey
FORTUNE: The graphic above comes from a survey of 9,766 so-called mobile information workers in 17 countries conducted last quarter by Forrester Research for its usual target audience: corporate chief information officers.
One of the questions Forrester was trying to answer is whether the BYOD (bring your own device) trend -- a movement that has undermined the CIOs' MOREPhilip Elmer-DeWitt - Feb 4, 2013 1:40 PM ET
For what it's worth, iPad tweets outnumbered Kindle 7:1, Google Nexus 18:1, Surface 50:1
FORTUNE -- I can't vouch for the accuracy of the information in this chart. The nominal source -- A.X. Ian -- describes himself on Twitter and other venues as "Purveyor of pseudo-random ideas. Information massage therapist. Always prolific, seldom profound."
But the ratios square with other signs we've been seeing -- including store traffic -- and bode better MOREPhilip Elmer-DeWitt - Dec 26, 2012 5:47 PM ET
Apple dominates tablet sales. Now Microsoft is going after the iPad head on.
FORTUNE -- Apple and Microsoft's relationship has had more twists and turns than Liz and Dick's. The two have been bitter rivals, vital partners -- even coolly indifferent. Microsoft's new Surface tablet could change things again. Apple's iPad has some 55% of the market. Amazon (AMZN) and Google (GOOG) have largely offered cheaper alternatives to compete. But Microsoft MOREJP Mangalindan, Writer - Dec 14, 2012 5:00 AM ET
Meanwhile, 44% of tablet shoppers plan to buy an iPad versus 24% for Kindle Fire
FORTUNE -- Consumer preferences in one of this holiday's hottest categories -- tablet computers -- shifted pretty dramatically between the third and fourth quarters, according to a new survey of U.S. households with broadband access published Thursday by Parks Associates.
Among its findings:
For the first time, more U.S. broadband households plan to purchase a tablet for the holidays MOREPhilip Elmer-DeWitt - Dec 13, 2012 5:10 PM ET
A survey compared sales at an Apple Store and a Microsoft Store in the Mall of America
FORTUNE -- On Saturday we posted side-by-side videos showing Black Friday shopping activity at an Apple Store and a Microsoft Store in Lone Tree, Colo. The videos left the impression that there was a lot less shopping going in the Microsoft Store.
Thanks to Gene Munster's team at Piper Jaffray, we can support that impression MOREPhilip Elmer-DeWitt - Nov 26, 2012 6:05 AM ET
Also: Microsoft's Surface tablet reviewed, and two reasons Facebook is turning things around.
Microsoft dives deep to surface a hit [WIRED]
This is a great device. It is a new thing, in a new space, and likely to confuse many of Microsoft's longtime customers. People will have problems with applications — especially when they encounter them online and are given an option by Internet Explorer to run them, only to discover this MOREJP Mangalindan, Writer - Oct 24, 2012 1:54 PM ET
In just a few weeks' time, the three-way death match for the future of the mobile operating system has shifted dramatically. Here's where Apple, Google and Microsoft stand now.
By Kevin Kelleher, contributor
FORTUNE – In a world increasingly going mobile, platform is destiny. The operating system will determine who rules -- or at least who has a seat at a lavish feast. Whether manufacturing phones or tablets, selling mobile ads or MOREJul 16, 2012 8:44 AM ET
Get out the sandpaper. Apple is said to be manufacturing the tablet Steve Jobs trashed.
FORTUNE -- Rumors that Apple (AAPL) was working on a smaller version of the iPad are nothing new. The Wall Street Journal reported back in February that Apple was testing such a thing and Daring Fireball's John Gruber gave his insider's view in an April podcast:
"What I do know is that they have one in the MOREPhilip Elmer-DeWitt - Jul 4, 2012 6:24 AM ET
Two mythical beasts lock horns
FORTUNE -- When it comes to puncturing bombast and anti-Apple FUD (fear, uncertainty and doubt), nobody is sharper than the Macalope, Macworld's longtime comic columnist. In Monday's post, the mythical beast and his old friend the Winotaur debated last week's event in which Microsoft (MSFT) unveiled its answer to Apple's (AAPL) iPad. An excerpt:
MACALOPE: Hey, what's with not allowing anyone during the hands-on to actually, well, put MOREPhilip Elmer-DeWitt - Jun 26, 2012 8:33 AM ET
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