The next version of Windows Phone having lot of features. In that we already now few things which are officially announced check here http://shareourideas.com/2012/06/25/windows-phone-8-new-features/.
few features which we already know is,
2) New Start screen
3) MicroSD Support
4) Multi-Core Chipsets
5) IE 10 and more
for two days there are few rumors about Screen Capture in Windows Phone 8. If it is true it will be awesome. Because most of the users and developers and me waiting for this feature from long back. In that rumors there saying that if we press Window button (Home Button ) and Camera button at a time. Then it will take a screen shot of current visible area on the screen. It will be very useful for developer to find the screen design issue and fix them immediately.
Windows button + Camera button
There few other rumors saying now we can also install XAP files which are placed in SD card. Because Windows phone 8 will support SD cards. So there is no need of uploading to market place for test distributions (it just rumor, not yet confirmed) .
To get more details of the new Windows Phone 8 please check with this page http://shareourideas.com/category/dotnet/windows-phone-developer/