It's changed in the states, you don't need to go to the FSDO anymore, just find an examiner give him $50 and he will issue a temporary airmen certificate and the FAA will post your card within 120 days.
As far as I am aware if your licence number has changed (including the letters) then you need to get you FAA cert changed. This can now be done by the CAA for a fee I believe if you visit them.