Just hold down Ctrl button while scrolling with mouse wheel… I have tested this (non exhaustively) on Revit 2013 and Windows 7, and it works fine on the following dialogs:
- the Properties Palette (wow!)
- the data section of the Type Properties (Edit Type) dialog
- Family Types
- the Family Parameters part (lower section) of the Family Category and Parameters dialog
- IFC Export and Import Options dialogs
- Fill Patterns settings
- Sheet Issues/Revisions
Thanks to this tweet for the heads-up:
@paulfaubin discovering #revit tricks! Ctrl+scroll on family type window to zoom in and out.
— Matias Cena (@onbeesknees) September 18, 2013