In Windows 8 adding an SD card to the Windows Music, Videos and Pictures libraries was a bit of a hassle. I wrote up a guide that lays out the steps you need to get an SD Cards content to show up in the built in Windows libraries. With Windows 8.1 things are a lot easier, there is no need to use Disk Manager you can simply add them from Windows Explorer.
The best way is to go to the SD Card in Windows Explorer, create Music, Pictures and Video folders and then right click on one of the folders and select Add To Library and pick the relevant folder. The content will then show up in the built in Windows 8 apps and in Windows Explorer.
It’s much simpler than in Windows 8 and for small sized devices like the Surface RT the SD Card is a great way to expand the storage.