Can you make a living writing books?

I was going to post about something entirely different today (it being 10/10/10 and all), but then I read the hilarious Maureen Johnson's post from Friday about whether or not it's possible to make a living writing books.

Maureen is the author of one of my favorite YA books of all time, 13 Little Blue Envelopes (and I'm excited to learn from her website that a sequel is arriving in May 2011).

I have to quote this passage from her Friday post that made me snort:

The reality is that the VAST MAJORITY of book writers do not make their living solely from writing books. The reality is that many advances are small, and you only write so many books in a lifetime (with the possible exception of V.C. Andrews, who has written over sixty books since her death as opposed to the six or so she wrote while alive, which is VERY IMPRESSIVE WORK).


Well, actually there were lots of passages that made me snort.  Go read it.  No, wait!  Come back. There's a question below: 


Are you an as-yet-unpublished writer like me? Do you think you'll ever make a living writing novels?  Or even nonfiction?