While I personally agree that "personality can and does change" and that such changes have the potential to trump so-called "external" factors, the research cited in this article doesn't seem to pack much of a punch.

Furthermore, I think that there are some major obstacles in the way of this kind of research in general. The average person's concept of what shapes one's personality is still heavily influenced by poorly understood notions of genetic determinism, philosophically naive definitions of free-will, and lingering ideas about human beings possessing a "soul" (even if such ideas are subconscious or secularly re-imagined).

Until there is a significant paradigm shift in those respects, I don't think we'll see the support or funding necessary to produce studies that yield actionable data.