Full disclosure: I haven't actually listened to the commentary yet.
Folks have mentioned that it was the Moff that was responsible for resurrecting Jenny.
To me, this is just another example of why he is a writer that I admire.
I don't see it as a sign that he prefers the young, perky blondes (although having seen his work, I have no doubt that he does like them).
I see it as a sign that he sees so much potential in the character. Having her alive in the universe is a Good Thing. There are stories that could be explored that touch her or are touched by her. Another writer may want to take that hook and run with it in the future, and you have to have her live in order to have that potential. It speaks of a wider universe than just the Doctor's story. I love that; it's practically inspirational (and feels like an invitation to go on and write myself).