Today at the Microsoft Professional Developers Conference (PDC), Microsoft Corp. showcased how developers can build applications in the cloud to power rich, immersive device experiences. In addition to the developers in attendance at the company’s corporate campus in Redmond, Wash., the event was broadcast live over the Web, and reached more than 20,000 developers at over 200 PDC events held around the world.

During the keynote address, Microsoft CEO Steve Ballmer and Server and Tools Business President Bob Muglia showed how the company is advancing the Microsoft platform, spanning the PC, phone and cloud. Microsoft specifically highlighted the momentum of Windows Azure, Windows 7, Internet Explorer 9 and Windows Phone 7 and the opportunity for developers today and in the future.

“Microsoft is combining the power and reach of the cloud with both Web and local device experiences,” Ballmer said. “There has never been a better time for developers to bet on Microsoft.”

Customer Momentum

Since the commercial availability of Windows Azure was announced earlier this year, Microsoft has seen strong growth with close to 20,000 applications to date. Demonstrating its RenderMan application during the keynote address, Pixar Animation Studios showed how it intends to use Windows Azure to more efficiently manage compute cycles by scaling as needed, helping improve project performance and eliminate costly back-end infrastructure.

NVoicePay, a key technology partner of Automatic Data Processing Inc. (ADP), is using Windows Azure and SQL Azure to provide medium-sized companies with the ability to pay invoices electronically and via a desktop PC or a mobile device.

“Building a mission-critical B2B payment network would have been nearly impossible without the low-cost, pay-as-you-go access of the Windows Azure platform,” said Karla Friede, chief executive officer of NVoicePay. “We could not have built our network at this speed and cost without it.”

Microsoft also highlighted that over 70 partners — including Twitter, Facebook, and Amazon.com  — representing more than two-thirds of active Web traffic are building on the capabilities in Internet Explorer 9 and HTML5. Since the launch of Internet Explorer 9 beta in September, there have been more than 10 million downloads, making it the fastest-adopted version of an Internet Explorer beta ever. The company also highlighted a growing list of companies that are betting on Windows Phone 7, including PopCap Games Inc., Intuit Inc., Amazon.com and Facebook. Further, Microsoft announced that the Windows Phone Marketplace will launch with more than 1,000 quality games and applications that extend the unique user interface and functionality of Windows Phone 7. The Windows Phone Marketplace will be open for application submission on Nov. 3.

The Most Comprehensive Operating System for Platform as a Service: Windows Azure

With the capabilities in Windows Azure, Muglia showed how developers can apply their existing skills to build new types of business applications, consumer Web applications and commercial ISV offerings.

“Only Windows Azure delivers general-purpose PaaS, which gives developers the breadth of services needed to allow them to focus on their applications and not the underlying infrastructure or virtualizing machines,” Muglia said. “Imagine having all of the IT infrastructure, hardware, OS and tools you need to support an app just a few mouse clicks away—it opens up so many possibilities for developers worldwide. We are looking forward to seeing the amazing things our customers will build on our PaaS offering.”

The On-Ramp to PaaS: Moving Applications to the Cloud

For existing applications, one option for customers is to move workloads to the cloud, using virtual machines to help lower traditional cost and management burdens. Today Muglia announced two new Microsoft capabilities for Windows Azure to enable customers to get on the path to platform as a service (PaaS): Windows Azure Virtual Machine Role and Server Application Virtualization. Windows Azure Virtual Machine Role gives customers the ability to run an instance of Windows Server 2008 R2 running in Microsoft’s cloud, making it easier for developers to move applications to the cloud. Server Application Virtualization gives developers the ability to transfer application images to Windows Azure, harnessing the underlying management capabilities of the platform.

Enhancing and Transforming Applications in the Cloud

Microsoft announced a number of Windows Azure services that also help developers create rich cloud applications that open up new business opportunities. To enable this, Microsoft introduced the Windows Azure AppFabric Composition Model to speed the process of assembling services by providing critical application deployment and management capabilities. To better connect developers to customers, Microsoft announced the Windows Azure Marketplace including the new DataMarket (formerly “Project Dallas”), offering premium and public demographic, financial, mapping, and entertainment data and other content. Commercially available today, the marketplace features more than 35 providers currently offering data subscriptions.

Windows Azure scales to projects and businesses both large and small, including mobile applications that require an easier and lower-cost means to experiment and build prototypes. As part of Windows Azure enhancements unveiled today, Microsoft made available the Extra Small Windows Azure Instance that eases the process of development, testing and trial. Priced at $0.05 per compute hour, this new offering lowers the barrier to entry for developers who want to run smaller applications on Windows Azure.

Complete information about the Windows Azure roadmap announced at PDC, including new features and capabilities, can be found here.

Delivering Cloud Connected Device Experiences With Windows 7, Internet Explorer 9 and Windows Phone 7

Ultimately, a primary role of the cloud is to deliver the best end-user experiences that span multiple devices, form factors and screens, regardless of whether people are at work, at home or at play. Microsoft gives developers the ability to treat both cloud and client applications as first-class citizens and deliver great device experiences that love the cloud. The rapid adoption of Windows 7 and Internet Explorer 9 creates new opportunities for Windows developers, especially considering that Web browsing is the No. 1 activity people do on Windows 7. The opportunity for developers to build applications for Windows has never been greater. Windows 7 topped 240 million licenses in its first year, and developers will drive a wave of new Windows applications that span different platforms through HTML and JavaScript, and run on cloud platforms such as Windows Azure.

At the PDC, Microsoft underscored its continued commitment to HTML5 and showed how developers can fuse the full hardware acceleration and site-centric design in Internet Explorer 9 to tap into the power of PC hardware, transforming their websites to feel more like native Windows applications. As part of the ongoing commitment to standards and “same mark-up” on Internet Explorer 9, the company also announced the availability of Windows Internet Explorer 9 Platform Preview 6, available for download today here.

The increasing power and accessibility of rich devices, combined with the ease of application development on Windows Phone 7, has driven more than half a million downloads of the free Windows Phone Developer Tools to date. Many of the same skills, languages and tools used to develop cloud applications on Windows Azure have come to Windows Phone for apps and games.

Extending the PDC Globally

Developers tuning into the PDC online and at PDC events around the world will have access to over 100 hours of live and on-demand technical sessions and Channel 9 interviews, covering Microsoft technologies such as Windows Azure, Windows Phone 7, SharePoint, Internet Explorer 9 and Visual Studio as well as industry languages and technologies such as PHP and HTML5. PDC keynote addresses and technical sessions can be accessed here.