Posted from 20,000 ft on my iPhone so forgive any typos.

Googler Jade, who seems to be everywhere these days doing everything, just posted these notes about an upgrade to the bulk tool:

Importing a spreadsheet to the bulk upload tool is now improved. Now, when you import a file, you’ll see a preview of changes that will be made and be able to cancel out any unintentional changes. We hope this allows you to better manage information on your business locations.

A few more details–

The import preview will have:
A summary of the total number of locations included in your account prior to upload and the total number of locations in the file being imported.

A series of tabs with the type of change your current import will have on your account and the number of locations that will be changed in each. The types of changes that are listed are: new, changed, missing, ignored, and unchanged. Please see our Help Center for a more detailed explanation of each type of change.

The tabs make it much easier to see exactly what changes will be applied to your account. If you see an unexpected number of locations in a tab (more “new” locations than you mean to add, for example), you can investigate further before applying any changes. You can read some tips on troubleshooting an import file here.

Please note that store codes are now mandatory to enable this feature. Learn more about the new improved import process.