Microsoft has updated its Visio Stencil for Office 365 that includes a number of symbols for building diagrams related to Office 365. The stencils can be downloaded here.
The stencils seem to work much better in this version in that the captions appear at the bottom instead of in the middle and they work properly with themes.
Old Version
New Version
However, I also notice that some of the shapes from the 2012 and 2014 versions have not been carried forward so you may still want these versions of the stencil and they are still available for download.