When doing mass property updates I copy and paste from the columns and do any needed rework in Excel. Then I copy and past the entire column back into the Update Property wizard. It would be nice to be able to do this from the Rename dialog as well. If I could select the entire New Name column I could do any needed rework in Excel and then paste back into the column.
Note that I'm using Excel for more than a find and replace. A find and replace in the dialog would be nice as well but that's already a wish list item.