There is a rumor that Windows Phone 7.8 will arrive on 28 November or in December, but may be someone can't wait and want it right now.
There is a Windows Phone and Android modifier society call XDAdeveloper. They cook a ROM that modify some part of the system and serve to someone who want some customize part. And there is a Windows Phone 7.8 update ROM and this is the list for those device that can flash the phone and install this ROM. Remember that install the ROM is almost same with JailBreaking the iPhone. There is a risk to make your phone as a brick, if you fail to follow the installation rule.
CAUTION : THERE IS A RISK TO MAKE your Phone AS a Brick, if you don't follow every step.
CAUTION 2 : There is a rule that it may use on what company bootloader, notice it first and make sure what is your bootloader.
The phone list that can install Windows Phone 7.8 update, click and follw
If you used to use Android or use jail breaking on iPhone, you will easily to do this. I suggest that anyone who don't familiar with this stuff. Waiting the official update is a good choice.
Thx : winsyde