I don't want to start a flame war over this, but anything that allows the peons of the world to gain knowledge is good. I'm very glad that O'Reilly allows knowledge to be had for free, and I'm sure it benefits them is some way, even if it just brings them good karma.
Lets not get started on software patents. :-) If the lawyers had their way, we would have to pay for breathing air, and a few fat cats would get rich, while the rest of us struggle for a breath.
There is a saying from the Tao... " it isn't worth a thing, unless it is freely given"
Is it a better world if the poor in undevloped countries ( and even the poor in the US :-) ) have access to the books? Do we advance more as a civilization by restricting knowledge to the 1% who can afford to pay for the numerous books needed nowadays?