Redmond hasn't yet promised a release date for Mango, but last week it started sending out invitations to a "VIP preview" of the operating system upgrade on May 24, according to WinRumors and other sites. Also last week, an initial batch of Windows Phone 7.5 features was revealed unofficially by the Windows Phone Dev Podcast, as we review later in this story.

Now, Paul Bryan, a Senior Director of Business Experience for the Windows Phone team, has disclosed more Windows Phone 7.5 goodies via a new posting on the official Windows Phone Blog. Among them, Bryan confirms, is the previously rumored integration of Microsoft's SkyDrive into the smartphone operating system's Office Hub (right).

Other enhancements tipped by Bryan target email. For example, he writes, users will be able to pin a selected email folder to the start screen for quick access. "This could be an email folder for a specific project, from a specific group or person (like your boss), or an RSS feed youve set up in Outlook," he explains.

Bryan's posting adds that Windows Phone 7.5's inbox will allow viewing emails by conversation (below). In addition, he said, smartphone users will be able to search connected email servers (e.g. Exchange Server) for older messages that are no longer stored locally, "giving you ready access to all of your email."

Windows Phone 7.5's conversation view (left) and Lync capabilities (right)
Source: Microsoft

It's further said that Windows Phone 7.5 will, via a downloadable app, provide unified communications capabilities in conjunction with Microsoft's Lync product. Users will gain instant messaging plus the ability to see the presence of their co-workers (above right), according to Bryan.

Bryan adds that Windows Phone 7.5 will include new security features, as follows:

• complex (alphanumeric) password support
• information rights management support for protecting emails and Office documents
• support for access to hidden corporate Wi-Fi networks

As indicated earlier, other new Windows Phone 7.5 features were discussed last week on the Windows Phone Dev Podcast, which, despite its official-sounding name, the Windows Phone Dev Podcast is produced by third parties -- Ryan Lowdermilk, a software consultant for Arxis Technology, and Travis Lowdermilk, a web/database developer for the Kaweah Delta Health Care District. The duo cited "screens we were given" (below) as indicating that the updated smartphone OS will include turn-by-turn navigation, texting via voice recognition, Bing searches via a phone's camera or microphone, plus improved SkyDrive and Windows Live Messenger integration.

Windows Phone 7.5's turn by turn navigation (left) and podcast support (right)
(Click either to enlarge)

Some of the new features in Windows Phone 7.5 highlighted by the Windows Phone Dev podcast will merely bring the Microsoft smartphone operating system into parity with what is already offered by Google's Android. For example, a turn-by-turn navigation feature (above left) will provide voice guidance while driving, plus maps that can always face north or rotate with the direction of travel. In addition, it's said, Windows Phone 7.5 will feature on-device podcast support (above right).

But, the screens suggest, Windows Phone 7.5 will also leverage Microsoft's TellMe voice recognition services to permit hands-free texting (note the "speak" icon in the image at left below). Additionally, it's said, the operating system will include new Bing Audio and Bing Vision services (below right).

Hands-free texting (left) and audio-visual search (right)
(Click either to enlarge)

Bing Audio search will apparently operate similarly to an existing third-party service, Shazam. Users will be able to hold their phones up to a radio or other device playing recorded music, at which point the search engine will attempt to identify it.

Meanwhile, Bing Vision will apparently be a search service that uses a phone's camera. It's said users will be able to scan barcodes, Microsoft Tags, QR codes, CDs, DVDs, and (via optical character recognition), even text.

Jonathan Angel can be followed at www.twitter.com/gadgetsense.

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