Hello shas123,
Hmm, since your wife is a US Citizen, couldn't you file for AOS based on marriage? I presume you've filed your 485 via employment, correct me if I'm wrong.
Cross chargeability is used when an applicant is married to a person who is born in a country that is not subject to retrogression. If you see our thread:
http://boards.immigrationportal.com/showthread.php?t=189753&highlight=cross+chargeability you would notice that all of us on here are EB2 applicants, wherein the derivative applicant, the beneficiary, has nativity of a country that has visas currently available as published in the monthly DOS visa bulletin. None of us are married to US Citizens, and in all our cases, our spouses are derivative applicants who have been born in non retrogressed countries (not India or China). Note that this goes by country of birth and not country of citizenship. Cross chargeability also applies if the primary applicants parents (either one) have non retrogressed country nativity, but I'm not too certain about those specifics.
I'm not sure that Cross Chargeability applies to your case, since your wife is a US Citizen. In your case I believe it would be a straight-forward AOS based on your wife being a citizen of the United States, green card via marriage.