Google is testing showing the number of views or impressions on reviews within Google Maps and local results. Thilo Corneille posted a screen shot of this on Twitter, it is in German but the arrows point to the word "views" so "212 Aufrufe" means 212 views and "248 Aufrufe" means 248 views.
Here is the screen shot:
I cannot replicate this but if you go into a local result, click on the reviews and then click on the name of the person who left the review, you might be able to see the number of impressions or views that reviewer saw for each and every of their reviews.
I cannot replicate this on desktop or mobile.
Forum discussion at Twitter.