I'm currently in the middle of a same day turnaround to PVG and wanted to confirm that everything JIX mentioned was spot on. In less than an hour, I had deplaned, cleared immigration/customs, got my boarding passes, went through security again, and made it to the gate.

I was able to check in online for my return flights before I left the US, but wasn't able to print those boarding passes from the kiosk in DTW...it would only let me reprint the BP for my flight from DFW to PVG.