There is currently a lot of mud-flinging going on regarding what people can or cannot do with Minecraft, specifically if they can make money with it.
This video here sums the situation up best:
Does this affect us? Most likely not. We are not charging hundreds of dollars for anything. But since there is so much talk about this right now and there are a lot of questions, I thought I let you know. If there are any changes that affect us, I will let you guys know.