Maybe they might do something about churning in the next year or so, but it is probably not as big of a problem for them as you might think, i.e. for every churner there may be 10 people who get the card and keep it, maybe even more. I noticed my friend using an AA Citi card to pay for our lunch the other day and asked her how long it took to get her 30K miles and she had no idea what I was talking about; she has had the card for several years. In addition, while most churners pay off their balance in full, a lot of other people do not, and the interest rates can be pretty high on mileage credit cards. So I think the impact of churners to Citi is minor, otherwise they would prohibit the practice.