Locally stored files for the Revit help system (for offline access) are now stored in this location: C:\Program Files\Autodesk\Revit Content 2015\Help
UniformatClassifications.txt and a newer version of the file, UniformatClassifications2010.txt, are now stored in this location: %ALLUSERSPROFILE%\Autodesk\<product and release>\Libraries\<locale and language>.
In previous releases, UniformatClassifications.txt was stored in this location: C:\ProgramData\Autodesk\<product and release>\UserDataCache.
If you put a copy of Keyboardshortcuts.xml in the UserDataCache folder, those custom keyboard shortcuts are copied to the user profile folder when a user first starts the software. See Important Files for a Revit Installation.
Software patches and updates are now managed using Autodesk Application Manager instead of Live Update.