There's a SIM card booth in the arrivals hall at PVG (by baggage reclaim). They have gone up in price quite a lot over the last two years - used to be something like RMB150 (100 call credit, 50 for the SIM), now they want something like RMB200 or more (and the SIM is 150 or something giving you only a small credit). But it saves a lot of hassle lining up at a mobile store in the city (which took me over 90 minutes a couple years ago - tried that once and never again). Sometimes they ask a price a bit higher, but they do seem to negotiate. I still don't know if they just pocket the higher price.

IIRC they also ask you to hold your passport up to your face and take a picture of you + passport. That's just a fast way of them being able to do whatever registration they need to do. In a proper city store the registration takes ages and they have to photocopy your passport etc etc.