Amex - Pay it / Plan it

I was just checking my Amex for the recent months statement and it came up with information about their new pay it/plan it options.
Basically any small charge (under $100) you can ‘Pay it’ now if you want to pay a particular small charge early.
For charges over $100 they are offering a Plan it option where you can arrange a monthly installment plan for a particular charge. It looks like 3/6/9 months are the options that are offered. “Plan It allows you to create a payment plan for qualifying purchases, subject to a plan fee. This fee is a fixed finance charge that will be charged each month that a plan is active.”

I don’t have any charges over $100 on my card and I always pay my CC in full unless I’m taking advantage of a 0% offer, but I was curious what the monthly fee might be.

It’s certainly an interesting new feature, but I can’t think of any way I might find it useful unless the fee is extremely low.

[Admin Edit: Made this post into a Wiki]

Link to the FAQ: