Another unique advantage is that Room 77 is the only site to allow users to sort hotels by their TripAdvisor ratings (other than TripAdvisor itself).

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TripAdvisor Media Network (tripadvisor.com) gathers and publishes user-generated content such as hotel reviews that travelers use for research prior to making bookings, and generates revenue from advertising.

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To that end, today TripAdvisor launched a new rating service called TripAdvisor Green Leaders, in partnership with Energy Star, the U.S. Green Building Council and the United Nations Environment Program.

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