Microsoft's Windows Phone 7 operating system often seems like a breath of fresh air compared to the usual grid-based array of icons on competing operating systems like Apple's iOS and Google's Android. The sleek Metro UI interface, Live Tiles, and even the "cutoff text" gives it a unique look in the smartphone space.

However, despite Microsoft's efforts to innovate with its latest smartphone OS, it hasn't exactly seen sales success after nearly a year on the market. Microsoft CEO Steve Ballmer has lamented the slow start for the Windows Phone 7 on more than one occasion. Microsoft is now looking to reverse its fortunes with Windows Phone 7.5, codenamed "Mango".

Whereas most Android smartphone users have to play the waiting game to see if their device will support the next major software update (or if they will receive it at all), Microsoft's strict hardware requirements for Windows Phone 7 mean that Mango is now rolling out across all major U.S. carriers (AT&T, Verizon, Sprint, and T-Mobile). There are also a slew of new phones that are on the way with Mango preinstalled. 

Some of the new features in Mango include: 

Groups: You can now group your contacts (think Google+ Circles with Work, Family, etc.) in a Live Tile on the Start Screen

What's New?: Current updates stream in via text, email, or social networks like Facebook and Twitter

Multitasking: Mango finally brings "intelligent" multitasking to the table and operates similar to iOS and Android

New Bing tools: Local Scout, as its name implies, allows you to search for local places and activities. Bing Vision allows you to perform searches using your onboard camera and translate text.

Internet Sharing: Carriers can now give you the option to enable Wi-Fi hotspot functionality

Web Marketplace: Allows you to search and purchase apps from your PC and have them wireless install to your Mango phone. This video explains the feature in great detail. 

“One of the things I’m most proud about with Windows Phone is that we took a different approach,” said Andy Lees, president of Microsoft’s Windows Phone Division. “We looked around and saw that smartphones were largely becoming application launchers, and consumers were left to navigate a sea of icons and a grid of apps. We looked to build all the core things that consumers want to do directly into the phone, and focus it all around people – not icons.” 

Microsoft still has a long way to go to get people to take notice of Windows Phone 7.5, but the company is making sure that people that do make the leap are in for a compelling experience. It's great to see competition in the smartphone space, so hopefully the Nokia mashup will give Microsoft some stronger footing against Apple and Google.