Users have noticed that Google has been experimenting with different color stars in rich snippets for businesses. Typically, the star ratings on products and businesses in Google Local listings are rated with orange colored stars.
Recently, more users have seen ratings with green colored stars.
Its hard to say how colors will effect the likelihood of a click through or if it will even affect a users judgement of the product but it is worth testing in the Google’s opinion. We will keep you updated if there are any official changes of star colors in search results.