JoshUSCB,
Unfortunately there is no built-in field that provides the information you want. However by using the Compare Project versions utility you can see changes from one week to the next. With a little extra effort, either manually or using VBA, a flag field could
be set that acts as the main criteria for custom font characteristics.
Interestingly enough, many years ago I wrote a macro that does exactly what you are after. It compares two versions of a project file and highlights task field changes. It was developed before Microsoft added the Compare Project versions utility to Project
and the macro uses direct highlighting in lieu of creating a separate comparison file.
John