How to hide reference counts in VS2013?

I guess you probably are running the preview of VS2013 Ultimate, because it is not present in my professional preview. But looking online I found that the feature is called Code Information Indicators or CodeLens, and can be located under

Tools → Options → Text Editor → All Languages → CodeLens

(for RC/final version)

or

Tools → Options → Text Editor → All Languages → Code Information Indicators

(for preview version)

That was according to this link. It seems to be pretty well hidden.

In Visual Studio 2013 RTM, you can also get to the CodeLens options by right clicking the indicators themselves in the editor:

documented in the Q&A section of the msdn CodeLens documentation

Another option is to use mouse, right click on "x reference". Context menu "CodeLens Options" will appear, saving all the navigation headache.