I used Trip Advisor almost exclusively when I had a 12/11 night trip to Germany/Switzerland in Dec 2008. You have to read between the lines in many reviews since some people are just complainers. I was pleased that the 8 different hotels we stayed at were all either nice or very nice. Neither one of us had been to that area previously. None were in the category of "uh oh" or I would never stay here again. Most were nice/charming and one was more of a business type hotel.
I will admit that I kind of cringe or chuckle when I see some of the manager's replies to the comments. I think most would agree that you only write a review AFTER you complete your visit otherwise you risk consequences kind of like sending food back to the kitchen too many times.
Oh, I had a trip to Milwaukee and crashed at a hotel near the airport. I arrived late (1130pm+) and when I checked in and went to my room my door wouldn't open all the way. I heard a noise and then realized that SOMEONE was in the room. I went downstairs and only got a "Huh, someone IS in the room?". She then gave me a new room. When I wrote a letter they didn't offer me my money back but only a free room on a later visit.
Later when I thought about the experience I realized how dangerous it could have been if the person didn't have the inner lock enabled. What if I would have walked in on a sleeping lady or possible a person with a weapon? They could have easily assumed I was there to rob/attack them, especially if they were sleeping. I just didn't think the response from the desk person nor the hotel conveyed sufficient concern for the dangerous situation. Hmmm, maybe I should have written a review for that one.