I have been playing with the Metro apps in Windows 8 Release Preview. It is only a small thing, but I am impressed with the ease with which you can customise the Bing News app to add your own special interests. See the video below for a quick demonstration.
You will also see that I struggled to find out how to remove a custom section. This seems to be the way with Windows 8 in Metro: easy when you know how, but you have to figure it out.