I'm in the same boat - DS was born on 29 December and I still don't have a Medicare card. I got him seen at my local clinic yesterday on my card and the receptionist asked me to ring them and give them DS number when I get it, so I didn't have to pay. I am going to call Medicare this week, as I know that Centrelink has processed their part. I sent the paperwork in mid-January, so Medicare have had it for about 4 weeks...