Microsoft (NSDQ: MSFT) wants to fulfill the needs of mobile users’ work and personal lives on a single device, the company’s CEO Steve Ballmer said in a CTIA keynote today. The emphasis of his talk was on the company’s new enterprise products, but he went to great lengths to emphasize the company’s work to make Windows Mobile a platform which offers general consumers as much as it does the mobile enterprise market, saying that “We almost have to think of the mobile phone as a universal remote control for your life.” The keynote focused exclusively on the Windows Mobile platform, and features of and services for it, making no mention of anything Microsoft is doing for non-Windows Mobile devices or in mobile web services.

On the changing mobile market: Ballmer said the industry has changed significantly since he first spoke at CTIA in 2001. Devices have improved significantly, and “users expect more capable phones” that can do much, much more than make voice calls. He added that the phone will be the primary PC and internet device for a large part of the world, particularly in emerging markets: “The PC is the most powerful device, but the phone will be the most popular device.”

Integrating voice into content services: Most of Microsoft’s demo focused on its new products for the enterprise market, which offer IT managers better control over and support for their employees’ Windows Mobile devices. The company did, however, show off some of the more consumer-focused features of Windows Mobile, including the integration of voice messaging into Windows Live Messenger and the voice search functionality of Windows Live Search.

On-device search: Microsoft also showed off the Smart Filter feature of Windows Mobile, which lets users search for on-device assets by typing in the first few letters of its title. For instance, users can search for a specific music track with it, or use it to quickly access a certain content.

The 700 MHz auction: “No we don’t!” Ballmer said when CTIA president Steve Largent asked him if Microsoft planned to participate in the upcoming spectrum auction. Ballmer said that, unlike “some of our competitors,” Microsoft wants to be an enabler of other hardware vendors and service providers, and owning spectrum could bring it into conflict with those companies.

Mobile advertising: It “is going to be a great revenue source for all of us,” Ballmer said, once the industry figures out how to make mobile ads relevant and high-impact. He added that Microsoft’s making a strong effort in building up its advertising technology in general, and in mobile specifically through the acquisitions of MotionBridge and ScreenTonic.

On the importance of mobile to the future of Microsoft: Windows Mobile and mobility is “very important” to the future of Microsoft, Ballmer said, responding to another question from Largent, because of the financial opportunity offered by the huge number of subscribers and devices in the market. He reiterated the company’s vision of serving both work and lifestyle needs, saying, “We can’t serve customers’ broad desire to bring together enterprise, desktop and online if we ignore mobile.”

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