A thought for Gold Card holders wishing to cancel: don't forget that you'll lose your MR balance when the card is terminated, so make sure you transfer your MR points to your airline of choice before you ring Amex to cancel.
Also: I'm going to be needing a referral for the Platinum Card. If anyone has traded stuff with me in the past/passed advice to me by PM/got PM advice from me would like to do it, please just drop me a PM.