(Probably) not related to this, but during this holiday season has been the two first times during my 2 years in China that police have stopped me in street to ask my business.
First was when I was going back home, at the main entrance of the house. In addition to the regular security people, there was a policeman who wanted to chat me up.
The second time was going out of bus in a small city in Baoshan. That time there were several policemen outside, apparently checking every arriving bus and interviewing any suspicious people.
Both times I had a Chinese friend with me, so there wasn't much of a hassle.
The second time could have been tricky without Chinese speaking friend, because the policemen apparently spoke no English (not even "hello"), and my passport was in RP processing, so I only had the receipt for that.

