In my mind, there were always three justifications for the Centurion, and each of the cardholders invariably fit one category:

1. Pure wallet candy

2. Careful calculation of benefit value and found it to exceed $2,500/yr

3. Use of the card for the ultra-upscale benefits, such as yacht and jet charter, where not only is the annual fee a drop in the bucket, but the benefits far exceed the fee (though the benefits are applied to things that most cardholders don't even think about purchasing)

I think that the recent devaluations have probably only impacted the second category: those who figured out that $2,500 up front was worth, say $3-10,000 on the back end. Those who'd stay at the Mandarin Oriental anyways or those who purchase multiple lounge memberships, for example. A friend told me that his dad's card would pay for itself each year when he went to NYC for a week and stayed at the Mandarin.

So those who carefully plan how to extract benefits are the ones getting screwed, but by the same token are probably the least profitable of the three for Amex (since the wallet candy folks never use many of the perks and the ultra-wealthy spend in such large blocks that the processing fees alone are quite substantial.