Microsoft outlined details about the improvements done on SkyDrive for the upcoming Windows 8.1, including placeholder files, offline access, and file picker integration.
Placeholder files gives you access to your files and folders without downloading them, minimizing the use of local disk space and internet bandwidth. You’ll be able to see the basic properties and file contents and the files will only be downloaded when you access them. With offline access, you can mark the files or folders you need to access when you aren’t online. And if you’ve edited a file on a device, SkyDrive will automatically make this accessible for offline use. And file picker lets any Windows Store app save files to SkyDrive easily without added work. You can find out more information about these features here.