It has been my experience that trying to turn one's avocation into a vocation is most often a bad idea...
Perhaps it's inevitable that things will go to a pay-per-page-view model, but I believe that when and if it does it'll change the nature of Blogging markedly. Perhaps for the better, perhaps not, but it won't be just a hobby one does for fun anymore and that will change how people approach it, view it, and what kinds of people engage in it, read it, and what their expectations are.
Myria draws an analogy with Linux. I think this is a good analogy. Programmers supply labor to the Linux project derive an indirect benefit in that their reputations are enhanced. This in turn can raise their value in other contexts. My approach to Blogging is based on that model. Maybe because of my Blog, I will be in more demand as a teacher or speaker. As John Perry Barlow puts it, you do not charge for bits, you charge for relationships.
Discussion Question: Myria says that Blogging would change if people saw it as an occupation rather than as a hobby. How might Blogging be improved by having an economic incentive to attract readers? What would be the down side?