It looks Microsoft is testing a new build of "Mango" Windows 7 Phone mobile operating system with built-in Twitter functionality.
A few users on Twitter begun tweeting with the client label "via Windows Phone (via Windows Live)." Previously Microsoft had tested the functionality where the client label read "via Windows Phone (via Windows Live)INT."
Among the tweets, one is from the Microsoft Windows Phone 7 official twitter account, and another two from Ken Dacey and Christian K who are Windows Phone engineers.
Also, Microsoft is planning on shipping Windows Phone 7 "Mango" devices as well as the OS by September, confirmed by Microsoft's Imagine Cup Twitter account, reports Slashgear.
The tweet let the cat out of the bag saying that,
"Imagine Cup finalists ALL receive Windows Phone 7.5 Mango Release!!" "Each Student will get the phone by September!"
Mango brings 500 new features to the Windows Phone 7 platform, including Multitasking, IE9, OS-wide IM integration, deeper social networking and more.
At day 2 during the Worldwide Partner conference 2011 in Los Angeles, the Redmond company showed off new Windows Phone 7 devices by Samsung, ZTE, Acer and Fujitsu, and touted that the platform now has over 22,000 applications.