As expected, everything that Microsoft revealed to top developers has leaked in the wild. Firstly the SDK gets leaked by a WinPhoneViet and then
@AngelWZR decided to reveal all the documentation that MS gave to them. Although majority of the things have leaked already, those who are still looking to know more can download and play with the Windows Phone SDK. The SDK requires a Win8 PC and the processor needs to support HyperV if you want to run the emulator as well.
Was trying to download the SDK, but the website is giving poorest possible speeds, hence giving up for the time it leaks at a better sharing website. As soon as I manage to install it, I’ll try to spend some time with it to see if there’s more to cover.
Windows Phone 8.1 Dev Documentation