If your primary residence was in any stage of foreclosure in 2009 or 2010 and your mortgage was serviced by JP Morgan Chase, then it is not a scam. Your post card reads like others that our clients have received. Here is the link to the Office of the Comptroller of the Currency website discussing this settlement: http://www.occ.gov/topics/consumer-protection/foreclosure-prevention/correcting-foreclosure-practices.html. There is also a link to Rust Consulting's website.
This is not legal advice. You should consult a lawyer from your state and discuss your particular circumstances in order to secure legal advice.
This may be a scam but since you were instructed to do nothing, then do nothing. Whatever you do, do not NOT provide money or personal information if asked. You will be able to verify any claim you might have an no one should ask you for money.