Ballmer asked that attendees go out and create lots of apps for the Microsoft environment, promising that Microsoft would follow through with advertising that should boost the market for those apps. "We will do more marketing for the Windows 8 system, for Windows phones and for Surfaces," he says. "You will see our best work, and you will not be able to go to a magazine, to the Internet or turn on the television set without seeing our ads frequently."

In response to a massive Microsoft effort, apps available in its Windows Store have grown from about 1,000 two months ago to more than 10,000 today, according to the website , the sole purpose of which is to analyze the store's inventory. Still more than 85% of the apps are free, the site says.

Whatever success Microsoft has with consumers, it has a more difficult time with businesses, Golvin says. "What we've seen in our data, the enthusiasm for adopting Windows 8 especially in the enterprise is much, much lower than it was for Windows 7," he says.

That doesn't mean enterprises aren't keeping an eye on what Microsoft is up to, judging from attendees at Build 2012.

Preston Doster, a consultant with Slalom Consulting in Dallas, attended seeking more detail on how the pieces of the Microsoft puzzle fit together. Clients say that they're interested in the possibility of slates that can join enterprise domains for work purposes, Doster says, something iPads cannot do. That potentially gives businesses more control over Windows 8 devices, he says.