theoretically it may affect your credit scores; however, in my experience, it does not make a big difference. I've canceled a couple of credit cards, when I apply a mortgage, I still got a good rate.
not bad. + V4 e# ^; y, ?, @$ E' o- G4 m' P# N5 Q4 D! F, ?, e9 Z
but compared with other rewards cards, the rate of getting points is not good enough. But if you buy things a lot at their stores, it is very good.