Well they don't want to cancel your old card because they're afraid you'll ditch them completely.
I would have probably switched to Citi and taken both the Platinum card and the PM one to go along with it, but as it stands I'm not interested in using their cards at all.
P.S. Will they renew the Platinum card once it reaches the expiry date for those who currently have one, or are they just waiting till they all expire so the product can disappear completely?