Interesting article from Ars Technica, where an erstwhile-textbook-publisher explains why he started up Flat World Knowledge and how his idea of open-sourcing textbooks (and making them free on the web) is going to make him a ton of money.
http://arstechnica.com/articles/culture/flat-world-knowledge.ars/1
On a side note, it also explains why textbooks cost so much and why they're updated every year.
Here's an interesting related article:
http://news.slashdot.org/news/08/09/10/1556242.shtml
The comments on this one have actually got a lot of interesting points to make as well from some educated people who work in the industry (and, well a lot of crap comments too, but still!).