I visited China as part of my Japan->UK overland trip, and spent a few days in Shanghai after arriving from Japan on the ferry. The most noticeable thing about Shanghai is the pollution. While standing on the Bund, the Pearl building across the river was only just visible in the haze.
It's in the evening that Shanghai becomes special - the view across the river from the Bund is amazing, all the buildings are lit up, rather like Hong Kong (but not quite as good!), and the light show on the Pearl Building is pretty cool.
I took the train out to Shanghai airport, I wasn't flying anywhere but the Maglev train travels at 431Kph, so it was an opportunity not to miss! I also made it up to the 88th floor of the Jinmao Tower. The views are spectacular, and I even managed to spot the boat I had arrived from Japan on. However, the worst part was looking down the internal atrium from the 88th floor all the way down to the 55th floor. It took all of my nerve to look over the edge.
Crossing the road in China
Crossings without lights: (white stripes on road) elsewhere in the world you either a) wait until the traffic stops and then start to cross. b) step out when there is a gap in the traffic, and once you are on the crossing then any traffic will stop. These are the two rules. However in Shanghai this is not the case - cars etc. move across the crossing at ALL times, you do not have priority at any time.
Crossings with lights: (green and red men) elsewhere in the world, you wait until the green man, and then it is safe to cross. You have a limited time to get across. In Shanghai the green man means nothing - the red man builds up a glut of humans, that are released on the green man, and it is hoped that there are enough of them to overwhelm the cars, if not - the cars have priority.
None of the rules apply to bikes or mopeds - they can cross with you, against you, drive on the road, the pavement, up the wrong side of the street against the traffic. You name it - they do it.
I found myself in China again as part of my 'Silk Road' trip in 2008. The plan was to see the terracotta army, and then take the new train line into Lhasa in Tibet. However that's not what happened, as the day before I left the UK riots erupted in Tibet, and the Chinese authorities shut the border to Westerners.
So that meant as well as getting to see the terracotta army I made it to Yangshuo to see the wonderful karst peaks that surround the town. Yangshuo itself is very touristy with lots of boats bringing hoards of tourists down the Li river from Guilin. However it's still a very attractive town, and most of the tourist are native Chinese ones. You can get pretty much anything you want (and a few things you wouldn't) there.