As a restaurateur with two businesses listed on TripAdvisor, we noticed a change when Priceline bought TripAdvisor. Apart from the modernised interface, the slight colour change and a few other updates, the biggest change I noticed as a business owner was the introduction of paid-for listings.
I read a letter from Tucker Max in the book Choose Yourself! which I thought totally on point about dealing with negative online trolls. It was written to James Altucher about his blog, but can equally apply to any field where you get public feedback. Here is the letter, and I also recommend the book (link above).