Yes, Google Is Testing Green Star Reviews In The Search Results
Google says expect more experiments with the colors of the stars in the search results over the next few months. The green starts some of you are seeing is indeed a test.
About six-months ago, Google began testing color variations for the reviews stars you would see in the search results. Typically you would see orange colored stars next to sites that deployed review rich snippets, but sometimes Google tests different colors.
Over the past week or so, Google has upped these tests, showing mostly green stars as opposed to the orange/yellow stars. A Google spokesperson told us today, “yes, we’ve been experimenting a bit with colors there.” Adding, “you may see more experiments along these lines going forward.”
Here is a picture of the orange/yellow stars that you’d normally see:
Here is one of many pictures sent to me, this is from @WLau89, showing green stars:
Again, Google is constantly testing this and if you see the green stars, you are not alone.