It used to be that when a restaurant found that a restaurant critic was coming or when a hotel found out that a hotel reviewer would be staying they could make an extra effort to give the best possible experience. One of the changes that the Internet has made is that everyone eating at a restaurant and anyone staying at the hotel might be a critic. With the advent of sites like TripAdvisor.com the power that used to be held by the press is now held by the everyday consumer.
Many or most people who write reviews on travel review sites are honestly intending to help the people that will travel after them. They write honest reviews about real experiences. Granted what they think is dirty you may think is acceptable and what they think is wonderful food you may find uninspiring, but an honest review tells you some valuable information when put in the correct context. A thoughtful well written review is of particular value.
But, as Lord Acton once told us, "power corrupts and absolute power corrupts absolutely". Stories are starting to come back from hotel and restaurant owners of a darker side of TripAdvisor and other review sites.
We stayed at a wonderful hotel in Santorini called Villa Mathios. Our host was accommodating, gregarious and helpful. He told us stories of guests who he let use his personal computer to check their email. He let them check in before the official check in time. But when they went to leave they asked for a ride to the airport at 6:30 AM. That is not part of the service he provides. He runs a hotel, restaurant and even a travel agency but not a free taxi service. So even though they had had a wonderful stay they threaten to write a bad review of the hotel (and did so when he does not relent).
I love user contributed content, community and social networks. My day job is running online communities for many well known companies. But these sort of dark side of community stories show that there is still value in editorial opinion. There is still value in the opinion of trusted friends or trusted bloggers / podcasters.