Google My Business is now showing a new metric in the insights section of your Google My Business listings for your photos. Google will show you how many views your photos are getting compared to other businesses like yours.
To access it you go to Google My Business and in card view, click on manage business and then at the top click on the insights tab. Scroll down and you'll see the photos section for insights.
Here is mine for my company:
This section shows the number of photos associated with your listing and how often they’re viewed compared to photos of businesses similar to yours. The “Photo views” graph shows the number of times your photos have been viewed by Google users, and the “Photo quantity” graph shows the number of photos uploaded by you.
The dropdown menu in the top left corner lets you adjust the timeframe and see data from the last 7, 30, or 90 days. Hovering over a specific day on the graph shows you data for that day only.
The lines on the graphs compare your photo data with photo data for businesses similar to yours. For example, if you manage a restaurant, your business would be compared to other restaurants in your area. You may not see this information if there aren’t enough businesses like yours nearby. On the right side of the graph you’ll see the total number of photos based on the data points you’ve selected.
Forum discussion at Google+.