I either own or have preordered every single thing in every CDJapan recommendation e-mail. On one hand, that means the recommendation system is accurate, but on the other, it would be nice if they could account for customers purchases.
It recommends me types, except the one I bought. All the time. And also some old or obscure bands I didn't even browse for. The most weird thing was today. They want me to buy spiderman figure. Fail.