According to http://www.immigration-law.com/ ...
Updated 01/17/2002: Green Card (Plastic Card) Production Processing Times
AILA teleconference with the NSC indicates that the INS has approximately 142,000 cards in the production queue nationwide. Currently, it takes approximately nine months from the date of I-485 approval. The NSC hopes to have the nine-month cut in half by the end of January 2002.