The biggest changes in Microsoft Office 2013 stem for the additional cloud capabilities. While OneDrive (previously known as SkyDrive) integration at a basic level existed in previous versions, Office 2013 takes this integration so much further. Additionally, the new roaming capabilities are enabled when you are logged into your Microsoft account within Office applications such as PowerPoint.
Here are some articles and posts on Indezine that speak about OneDrive:
Share PowerPoint Presentations on Social Sites using OneDrive
May 4, 2013
Account Tab of Backstage View in PowerPoint 2013 for Windows
December 24, 2012
Sign and Switch Accounts in PowerPoint 2013 on Windows 7
December 22, 2012
Sign and Switch Accounts in PowerPoint 2013 on Windows 10 and 8
December 19, 2012
Manage and Remove Connected Services in PowerPoint 2013 for Windows
December 10, 2012
Add Services in PowerPoint 2013 for Windows
December 3, 2012
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