As much as I liked M on the Bund two years ago, even then it was getting mixed reviews. the view is a fantastic one though, so maybee get a drink there? I've only spent limited time in SH but a bite at the Italian restaurant in the Hyatt Pudong (56th floor?) mixed fresh ingredients and quality food with a fantastic view of the city (despite the smog). Apparently the view at the Cloud 9 bar (80 something floor) is even better.

I'm waiting on Moondog to give you some tips as he's spend some significant time in SH.