Ok, I have to be a bit harsh but here's the deal...
You're getting married and moving. What is more important you being able to live in China or being able to live with someone anywhere on the planet?
Indian's have been doing business and marrying in Shanghai for the last 100 odd years, ever since the Parsis started doing business in these areas. Some of them survived and some did not... some did well and some did not. There is no magical formula that says Indians will do well in Shanghai if they do these things.
There are a ton of IT people, jewellers, traders and people of Indian origin in Shanghai. Now, just because they're Indian does not mean they'll be welcoming to you and want to help you and be sympathetic towards your origins...
The net is a good tool to do research, but it does not beat some real life talking to people... make your decision based around people you know in real life. Does your fiancee have a network which will support her and you when you move to China? Are you capable of living in an environment where you may not have any friends or not.
Do you get along with the other Chinese in your Uni? If you did not, forget about moving to China .. they're just going to be more of them and most are going to be more unsophisticated than the ones you met at Uni. How culturally adaptable are you? Will you be able to eat noodles for breakfast, lunch and dinner? Or do you need your daal bhat every day?
Get your butt out of your chair and walk down to the Chinese embassy nearest to you and talk to them about the procedures and issues related to your marraige and your employment in China. They should have a Hong Kong "desk" which will be able to similarly help you with issues to both of you moving to Hong Kong.