JW Marriott Shanghai on Tomorrow Square is one of the shining stars of the Marriott chain. I just stayed there, and found it has maintained its standards. It is quite close to Le Meridien If you stay there, I recommend getting a room on the executive level. The service is superb, with breakfast, afternoon snacks, and evening appetizers.
Smog was very bad when we were there 2 weeks ago. I remember views being great from the 56th floor Executive Lounge,. On this trip, all we could see was white.