I won't try to summarize the debate in the forum--you should subscribe to the magazine so you can read it!-- but can't resist responding to Adam's question. For another response, have a look at the various points Denise Cummins makes here. As an adoptive mother and cognitive psychologist, she has a lot of relevant expertise and experience.
Adam's response is Yes--procreating is selfish, because (roughly) adopting benefits an existing child in need of parents, whereas procreating brings a brand new child into existence, a child who would not have been in need of rescue if they'd remained non-existent. And on the other hand, adopting provides just as much of the most important kinds of satisfaction for parents. So far procreating just sounds irrational. It starts to seem selfish if you add that people choose procreation (despite the superiority of adoption) out of some sort of selfish preoccupation with their "lineage".