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It can be shown by the mathematical economics folks that the free market leads to economically optimum results if and only if the goods in the market have certain attributes.
If goods do not have those attributes, the free market does not work with those goods in the sense that it does not lead to a good allocation of resources.
Intellectual goods do not have those attributes. Therefore the free market does not work for intellectual goods.
If we want to have optimal allocation of resources to the production of intellectual goods, we either need some mechanism other than the free market (e.g., patronage, probably by the government) or we need to pretend that intellectual goods DO have the necessary attributes. Our current IP law takes the later approach.
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Nearly every anti-current-IP-system opinion I've read (including the submitted article and most of the comments here so far) fails to propose how to achieve reasonable allocation of resources using some system other than the current system (except for RMS...he's one of the few who gets it--see below).
At best we usually get suggestions that creators of intellectual goods will find something else to do. For instance, musicians will give concerts, writers will make their living doing contract articles, programmers will provide customization or support, and so on.
Those suggestions are missing the point. When a great novelist is spending time writing articles, he's not writing his next great novel. When a great programmer is handling tech support, he's not writing great programs. Those resources are not being optimally allocated.
RMS has suggested that there be a tax on internet connectivity, with the money going to fund creators of intellectual goods, with distribution of the money based on the cube root of popularity.