One big difference between RB and Amex is that the former posts right into your CP account monthly, where Amex of course maintained their own rewards program, of which CP was technically just one member (probably getting 90%+ of the redemptions).
So at worst, one should lose the unused portion of the annual fee, plus a month's postings. And of course the bank is more likely to credit $10 for unused months ($120/yr). And you know, if they're cut off prematurely, they're more likely to give a 2% cash rebate for any purchases that can't be posted to CP (CIBC offers a 2% cash rebate card with a lower annual fee than Aerogold, so it must be do-able).
I think this is a safer bet than Amex was (and I have to decide soon what to do with my MR points).
andrew