Big announcement from the Windows Phone team – they’ve released the Windows Phone Mango OS beta along with the Windows Phone Developer Tools Beta 2 this morning.

The best part? If you have a developer unlocked Windows Phone device (that means that you’ve gone through the Marketplace registration and can currently deploy development apps to your device) you can upgrade to the Mango OS beta! The Mango OS brings a LOT of new features that I’ve really come to enjoy in the short time I’ve had to try it out.  Unified inbox, threaded messages, Windows Live Messenger support, Double-sided Tiles, contact groups and more! 

There’s also some goodness for students too – do you have a Dreamspark account? Do you have an idea for next big Windows Phone application? If so, submit your ideas to the Windows Phone team for a chance to win a Mango phone! Here’s how you do it:

  1. Make sure you’re registered for DreamSpark
  2. Download and install Expression Studio Ultimate and the new Mango Windows Phone Developer Tools (available free as a member of DreamSpark!)
  3. Get the free Sketchflow Template for Windows Phone and create a Sketchflow mock-up of your app
  4. Post the Sketchflow mock-up somewhere online and tweet out the link using the hash tag #WPAppItUp
  5. The WP team will review all prototypes and will contact the developers who submit the best ones and send them a special Mango developer device

Your next steps should be to download the latest tools, start exploring them, their features, and upgrade your phone to the new Windows Phone Mango beta OS. As an added bonus, just like Beta 1, Beta 2 supports framework multi-targeting, which allows you to keep on building great Windows Phone 7 applications today while giving you the ability to explore new features in Windows Phone Mango  and the WPSDK 7.1.

Also, for more information, be sure to check out Brandon Watson's post on the Windows Phone Developer Blog: