TERRIBLE PLACE !
I stayed at The Marriott Courtyard Embassy Row from 2nd to 7th nov 2012. The hotel is extremely noisy, I had to change rooms twice because the windows are not soundproofed. I endend up in one of the ground floor rooms the windows of which do not open and have thick pans. Otherwise it is unbearable, it is like having your bed in the street . 
WAKE UP CALLS FORGOTTEN : Twice the hotel did not wake me up and I had to rush to meet my appointments in ten minutes . Even after the first incident and my complaining at the front desk nothing was made to fix the problem, no explanation, no apology , no compensation , and same problem occurred again the following day ! They are really taking the guests for fools !
WIFI CONNECTION EXTREMELY WEAK: I was disconnected several times. It was extremely difficult to work as it was impossible to have a decent connection. Either getting disconnected or slow!
Very limited rooms service, only during the opening hours of the hotel restaurant and neighboring ones .
Stay somewhere else... there are several hotels in the neighborhood: Westin, Grand Hyatt (rooms viewing the lobby seem quiet), Fairmont, Ritz Carlton etc ... some others right in front such as Holiday inn , Homewood Suites ... but I did not test them .