What does this message mean? Also, it said document was mailed on Dec 23 2008, however, I still haven't received it today.
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Application Type: I485, APPLICATION TO REGISTER PERMANENT RESIDENCE OR TO ADJUST STATUS
Current Status: Document mailed to applicant.
On December 23, 2008 we mailed the document to the address we have on file. You should receive the new document within 30 days. If you do not, or if you move before you get it, call customer service.