First of all, let's start with the fact that the reason I was not in FB, Blogger or Picasa lately is that all of the above are blocked in China. I am not sure what's the deal with Gmail: it kind of works but is impossibly slow.
Skype works fine, though, and so does IRC, and ssh connections.
Another thing is that I am not sure to which extent I can quote people I came in contact with. I'll try not to quote anyone specific on anything other than neutral.
Many people have told us we need native guides everywhere in China, and we had them in every city at least for some attractions, and they were good, but not strictly necessary. I'd recommend them for visiting places where the major attractions are out of town and/or the transportation is not very good. Major cities can certainly be visited on your own.
For some reason almost everyone was concerned about us getting physically lost. In the noble art of reading a map somehow rare over there? They sure make maps.
The people speak English almost as badly as the Japanese, but seem to be a lot less stressed out about it. In general people are friendly but not very considerate.
You can't drive in China with a foreign driving license (or even a Hong Kong one), and it's for the best. The traffic is enough to drive anyone postal. The drivers, especially those of scooters and motorcyles, don't seem to be able to tell right from wrong, right from left, or red from green. Turning right on red appears to be legal; turning left on red, illegal but just as popular. This is not as terrifying as it sounds: Chinese drivers, unlike those of southern Italy, tend to do stupid things at reasonable speeds, and seem to be keenly aware that all the other drivers are likely to do similarly stupid things.
In general respect for the rules and the law is not high.
All the places where we went to appeared perfectly safe at any time of day.
For all the talk about the fake money, there was only one occasion when I felt any doubt about a bill. It was replaced by the salesperson without any trouble. Locals do check their bills though, so we did, too.
All the restaurant bills were ok, nobody tried to cheat even once.
The Chinese seem to have the same idea of private space as us (or at least as me). Every time I felt someone was entering my private space, they were doing it on purpose.
Public places have a lot of benches and other sitting space, very nice. Also toilets are widely available, and not nearly as bad as people say. Some of them have only holes, but most have at least one western-style bowl. Bring your own paper.
There are a lot of people employed as a decoration, just to stand there and smile at people or greet them or whatever.
Lots of police everywhere. They don't appear to be hunting dissidents or people who run red lights, but just stand there and guard inanimate objects that are IMO unlikely to be targeted by the enemies of PRC, such as benches, lightpoles, public toilets, etc.
The tourist information centers look, well, Soviet.
I am sure that people who know what they are doing can find whatever they are looking for, but for the first-time visitor: supermarkets are hard to find, and be sure to eat before 10 p.m., because after that it's hard to find an open restaurant. The Chinese usually have their dinner at about 6.
Shopping malls usually have some food stores, restaurants and food courts in the basement and on the top floor. Bottled water is widely available from many kinds of stores.
Decent coffee and black tea are not widely available in the cafes, but not hard to find, either.
There are many ATMs, and they work.