N-back news: Jaeggi 2011, or, is there a psychologist/​statistician in the house?

Following up on the 2010 study, Jaeggi and University of Michigan people have run a Single N-back study on 60 or so children.

The abstract is confident and the mainstream coverage unquestioning of the basic claim. But reading it, the data did not seem very solid at all—I will forbear from describing my reservations exactly; I have been accused of being biased against n-backing, however, and I’d appreciate outside opinions, especially from people with expertise in the area.

(Background: Jaeggi 2011 in my DNB FAQ. Don’t read it unless you can’t render the above requested opinion, since it includes my criticisms.)