Second the Mr&Mrs Bund and Din Tai Fung - you have to try the Shanghai soup dumplings.
There's a bar called Face in the French quarter set in a big mansion it's like transporting yourself to stockbroker's Esher with a huge lawn. That's a nice stop off after shopping.
Regarding beauty items, you can get huge bottles of Cetaphil (brilliant cleanser) from Watsons branches.
Avoid buying foundation as it's usually. I learned the hard way and several not-quite-right bottles of VitaLumiere....
Skin creams, well, it's mostly whitening and they are expensive.
Look out for Suqqu (brushes are amazing) and RMK though.
I would recommend massages while you are there. Hotels, little step in parlours, they tend to be very good and quite, er, intensive! Manicures and pedicures also are a very high standard.
I am SO jealous. I had to leave Asia before I was ready and constantly dream about the food and climate (and having a housekeeper....)