http://reason.com/archives/2014/05/26/irs-sets-sights-on-frequent-flyer-miles
I wonder if this will also affect credit card bonuses.
Conceptually, you could think of it as income when you get a cc bonus, in that you are being paid to use their card. However, if so, you should be able to reduce it by the amount if interest you pay on the card, since you should then think of it as a rebate of your interest.
For points for spend, it conceptually should be viewed as a discount on what you bought, just like cashback. So I'm not worried there. Once we get there though, why not view the bonus as a rebate on the initial required spend?
The real trouble in thinking about this, is that it isn't a business transaction. When you are given a cc bonus, it isn't because you are buying something--you're giving them nothing. It is because, as a wise colleague said to me, "if you aren't the customer, then you are the product." Do you pay taxes on something given to you to make you a product? I don't see why not, but it doesn't fit so well into the normal ways of thinking.