That is a good article. Though I'm perplexed by this line "About 90 percent of Serve customers are new or returning to AmEx, according to the company." So...what are the other 10%? Existing customers? Because returning would imply they aren't Amex customers at the time they signed up.

Also with that article, it's worth noting that since they classify Serve/BB under "Enterprise Growth", they reported a pre-tax write down of $419 million in the enterprise growth division in Q4 2015.