One more new feature in ILSpy - Analyze. It currently works with fields and methods. Simply right-click on a field and select Analyze from the context menu:
This opens the Analyzer view below the decompilation view (Read By and Assigned By are not expanded by default):
The same procedure also works with methods, however the analysis is different (Uses and Used By, I did not expand Uses because the Display method does indeed use quite a few other methods):
Basically, this brings you the "Find Usage" feature in ILSpy. To be added: support for properties and events.