FWIW, I've ordered from Affinity Alliance and received discounted cards, though it was not an experience devoid of eyebrow-raising moments. There's an ongoing forum thread on ozbargain which originally explained why the earlier IAIM membership was pulled (basically they got ozbargained), and has evolved into more of an 'ordering from Affinity Alliance' thread. There are others besides me who report successfully completed orders to date... if anyone is thinking of getting in definitely have a read of the thread and caveat emptor.
I can't post links so it's /node/142887 on ozbargain, or google "IAIM DISCOUNT CARD" and it'll be one of the top few results.