Annotating Visio diagrams with issues
One useful feature of Visio is the ability to add reviewers' comments and scribbles via the REVIEW tab.
In fact, this feature has been changed for Visio 2013 and is a replacement for the old mark-up feature that was present in the previous versions of Visio. However, the old feature is still present, and accessible via code, but hidden from normal users (unless they are added back in again with the Customize the Ribbon feature). There were some good reasons for Microsoft providing a different way of adding page and shape comments. For example, the new comments are also editable via Visio Services on SharePoint 2013, and the comments are actually associated directly with shapes. I have utilized the old mark-up feature to display issues, so that they do not become confused with other shape comments.
Normally, comments are assigned to the currently signed-in user or you can create them for the local user, which you can set by navigating to File | Options...
