Perhaps, but still, it seems like a lot of people are confusing the introvert <-> extrovert axis with the self-centered <-> socially-conscious axis. They are in fact highly orthogonal in my experience. At least insofar as it's possible to judge someone's psychology from a blog post, she would score far into the "self-centered" region of the latter axis, while being somewhere on the introverted side of center on the former... even if she doesn't recognize it.

I don't expect a leopard to change its spots, but at the same time I believe it's possible to consciously nudge yourself in one direction or the other on both axes.