Chris Anderson wrote a book called Free. It discusses the downward pressure information technology exerts on content. Background here.
The NY Times reviewed it and considered it sloppy, for a start.
Malcolm Gladwell reviewed it in the New Yorker and criticized the whole thesis.

Seth Godin disagreed with Gladwell, writing a post entitled “Malcolm is Wrong.”
Fred Wilson provides a VC perspective as to the use of ‘free’ in building market share.
Many other posts on the the topic of ‘free’ spiral out from these posts.