Microsoft started to push the mango version 7712 to developers today.

Wpmind found micro yesterday
Software has released a version 7712 mango update for a small number of developers on the connect site, including for Asus e600 and HTC
Upgrade package in ffu format of mazaa. However, developers do not need to worry. From today on, Microsoft will
The registered developer of the hub pushes the upgrade of 7712. If you are lucky enough, your phone will soon receive a prompt saying you can upgrade:

As with the previous upgrade method, you need to go to the connect site to download the new Zune (4.9.20.4) and the corresponding updatewp tool. Wait. Don't forget to download the corresponding Windows Phone SDK 7.1.Beta 2 refresh. The new SDK has made many improvements:

• First, all the APIs have been locked, which means you can use them to start development of official products.
• The simulator has the screenshot function. You no longer need to use third-party tools to capture images on the screen.
• Profiler has been greatly improved to help you better analyze yourProgram.
• Nuget tools can be integrated into the Windows Phone SDK.
• The marketplace test kit tool allows you to check your program before submitting the program to marketplace, so as to help you identify many potential problems and increase the chance that the program will pass the review.

Okay. What are you waiting? Go to the connect site to download the new SDK and Zune, and wait for the upgrade prompt on your mobile phone!

Message Source: Windows Phone developer blog