when the people who's applying for a B2 visa(tourist visa),there's also a line in the forms: Is your finance(e) in the States? and if u tickle this item,u'll get rejected 99% by the VO,for u have a intendency to immigrant; but as far as i know,u can fill in "no" and if the VO hasn't raised any problem on this issue during your interview,u can get pass and get the visa; it's kind of cheating,but it works.One of my co-workers get the B1 visa last month,and when she filled the forms,she said she's married,but in fact,she's single,while a single girl can easily be rejected to the States by VO,(thinking u guys may fall in love on Chinese girls and get them stay,) so from what i've seen,the Consulate in SHANG HAI probably not has the record of what GZ has. I'm telling u what things can be,not to encourage u to cheat,
