With Azure, Microsoft has a hedge against this disruption: It can make up whatever it loses in the personal computing space, and then some, by becoming a key cloud infrastructure provider for apps and services of all sorts, regardless of platform.
In Ballmer's vision, Microsoft is working to define the right balance between openness and a more proprietary attitude that protects the larger Windows ecosystem. The company's reluctance to release Office for the iPad, and its decision to use Office for the iPhone to push Office 365 sales represent examples of the latter strategy. But Azure represents the former.
Thursday's keynote included a demonstration of an iOS app being added to Windows Azure through a Mac. Though Microsoft representatives joked that founder and former CEO Bill Gates might descend from the rafters and kick the rival device offstage, the intermingling of Windows, OS X and iOS was striking.
Indeed, though tools familiar to longtime Windows developers were mentioned, Build was also about reaching out to the new breed of app-makers whose interests are more rooted in start-ups, mobility and social media than in classic Win32 software. The presentation included an appearance by Box CEO Aaron Levie, who talked about "a whole new Microsoft," and how open the company has become. Box's links to Microsoft will include Windows Azure Active Directory tie-ins to help authenticate users, and to make the sensitive content that Box hosts more secure. Other hooks between Azure Active Directory and third parties mentioned during the keynote included DocuSign, Google Apps, Salesforce.com, Evernote and even Amazon Web Services, Azure's nemesis in the cloud market.
Microsoft has reason to be confident in Azure. Satya Nadella, head of the company's Server and Tools division, said during the keynote that Azure supports Skype's 299 million users, 50 million Office Web apps, and 1 billion mobile notifications from Bing per month. SkyDrive, he said, has 250 million users, and Xbox Live has almost 50 million subscribers. In an important transition for Microsoft's long-term licensing strategy, the platform also has helped Office 365 go from one-time purchases to perpetual subscriptions.
Nadella said that more than 50% of the Fortune 500 uses Azure, and that its customer base of almost 250,000 is growing by around 1,000 a day. Despite this success on the larger marker, it was a strong statement that so many Microsoft products rely on the company's cloud platform. If the company uses Azure for so many critical services, Nadella implied, developers and customers can feel certain Microsoft's cloud is ready for prime time.
In addition to Azure Website and Azure Mobile Services, Microsoft also previewed an auto scale technology that allows compute capacity to be spun up or down based on definable parameters, and application access enhancements for Windows Azure Active Directory, including single sign-on for cloud-based applications.
Additionally, Microsoft released a preview version of Visual Studio 2013, a toolkit that helps developers write apps for Windows 8's Modern UI, and which company representatives demonstrated during Wednesday's keynote. Wednesday's upgraded developer tools also included a preview of .NET Framework 4.5.1.
Other keynote topics included a new advertising SDK for Windows 8.1, and an updated advertising SDK for Windows 8, as well as a preview of Windows Embedded 8.1 Industry.
Although Build has confirmed much about Microsoft's vision for the cloud and modern, multi-device mobile workflows, some questions are still unanswered. During the keynote, for example, Steve Guggenheimer, VP of Microsoft's developer and platform evangelism, noted that the Xbox shares a common core with the rest of the Windows ecosystem. The gaming platform's openness to third-party developers has been a subject of contention, and though Guggenheimer bluntly said, "Nothing to announce today," his reference to an ecosystem-wide codebase is sure to fuel speculation.