We live in the US and stayed for one night at Hotel O in early November. Looks like the hotel came under new management and has been completely renovated in Oct. 2012.
Our expectations were exceeded in every way with this hotel. The rooms were spectacular (beautiful modern designs with stunning color usage and fixtures). The staff were very friendly and helpful and spoke good english. The Louvre was around a 5 minute walk from the hotel and we were able to take the train directly from Charles de Gaulle airport to a stop that is around a 10minute walk from the hotel.
Overall - highly recommended. Looks like the other reviews on tripadvisor are from the previous hotel that was at this location.