I agree with TUP and Sampan. You really have to assess the source for these kind of things (ie. surveys. We've learned biases in surveys in the statistics unit in grade 9!) Although I frequent Chinese and Chinese/Canadian websites (xinhua, chinasmile, etc), I must say I have NEVER come across this wangyi site.
They also mentioned nationality, and think about it. Being a Chinese national gives you very few rights (not that most Chinese cares). You cannot hold dual citizenships if you have a Chinese citizenship (which many Chinese, particularly overseas, resent).
Yes, there is a strong public opinion in China that "The West is Great". That's one of the reasons China is experiencing a brain drain. The wealthy and educated of China flees to find a better life in the West (not so much freedom as wealth). As Sampan pointed out, the grass is always greener on the other side is definately a contributing factor.
One of the other reasons is that Chinese are discriminated against all around the world. This contributes to a feeling of self-hatred amongst some Chinese, particularly overseas Chinese youth. Thus they become "whitewashed" in order to try to change what their identity defines for them.
What you've heard about from Chinese nationalists, ie China is the best country in the world etc. is mainly coming from the uneducated portion of the population in China who has enough money to not worry too much about food, clothing, and bills, and not enough money to buy too many luxuries.
Frankly I see nothing negative about saying "Once a Chinese, always a Chinese". You simply just can't genetically mutate yourself to become caucasian, so why not accept the facts and be proud of who you are.
"Seriously, I didn't think so many people would want to be re-born somewhere else. "
I bet you that African and Brazilian mothers who have lost more than 5 sons wished they would live somewhere else.