Spent three nights there in Feb. '06. Stayed in Room 16. Although the water pressure was less than desireable, the staff was first rate, very quite location, relaxing grounds (with the exception of the periodic train signal, pool however is a nice respite), safe, secure, food very good and plentiful. Not a great deal to do outside the hotel but an interesting walk through a typical Indian neighborhood. Had a bit of a gout attack and the nearby pharmacy quickly produced the proper remediy at 1/10 of the cost back home.
As for the Park itself, somewhat sterile, but nonethelss facsinating and a welcome change from the major cities. Saw three tigers over the course of three days and the tigers could absolutely care less if we were there. Abundant wildlife to be seen and photografted. Be sure to take a bandana or other article to cover your nose and mouth as the dust is unbelieable. If you were contacts, by all means use your eyeglasses.
Overall, from what I was able to gather from other travelers staying at other hotels (including the Oberai), a great value in a tranquil setting, but still close enough to town to get a sense of the local surroundings.