For information regarding the Chinese drywall issue please go to www.drywallresponse.gov
The CPSC (consumer product safety commission) has released several documents (click on title for .pdf doc)
Interim Guidance - Identification of Homes with Corrosion from Problem Drywall
Interim Remediation Guidance for Homes with Corrosion from Problem Drywall
List of states where problems have been reported http://www.cpsc.gov/info/drywall/drywalldist.pdf
The vast majority of problems were reported in Florida with several other southern states experiencing problems also. Here is a picture showing the states with the largest percentage of reported problems.