I would highly recommend the Shanghai Expo. The best country pavillions to see are those with short lines. Unfortunately the US pavillion is not worth the wait. Lines are unavoidable, so take a book, backberry, or ipad.
Also highly recommended is taking a night cruise on the Huangpo River, as the entire city is well decorated.
(If this belongs in another forum, pls do move it)
Ajax
Iām going to SH on business in a couple of months and will take the opprotutnity to visit the sexpo. You say the queues are quite long. Would you be able to say just how long the waits were (ie how long was the wait to the China pavilion) and was it weekday or weekend that you went?
I canāt wait. I have some enforced fun coming up next week at the expo 
Hopefully weāll meet somewhere more civilised than the Expo, Elegua. Up there tomorrow for a week.
Mate of mine involved with the US pavillion said there was a big line outside, and when it didnāt open on time, the Chinese began abusing them as āfucking American capitalist pigsā. 
HG
As long as itās Mr. Fucking American Capitalist Pig. Anyway, it didnāt open on-time because weāre the Socialists now. They are the effin Capitalist Roaders.
Constellation? Followed by the SAIC center? 
We went on a rainy weekend, the crowd was judged to be light, only 300,000 people. No lines to get in, but all the pavilions have lines, 10 min to 1 hr plus. US pavillion had a line of 45 min, but was a disappointment. No chance to get into the Chinese pavilion, as have to book a day or so in advance. There was a line of 500 to 700 people for the Taiwan pavilion, they only give out about 100 or so tickets at a time. Still lots of fun. 