This article never comes out and says it directly, but it sort of has this tone like this is some sort of unusual thing. Hardly. You'd be hard pressed to find a successful web comic running for several years that hasn't put out some sort of book, or some sort of tangible, purchasable artifact. It's a great way to support your favorite comic while getting something nice back, if donations are too hard (or in some cases, not accepted).
(No disrespect to xkcd, and kudos on getting the NY Times placement.)
I agree, but I suspect most of them went through a traditional publisher. The big difference with what we're doing is that breadpig inverts the profit structure -- the artist (that is, xkcd) receives a majority of the profits from the book. We're aiming to deliver a high quality product similar to what you'd get from a 'traditional publisher' (we're using their suppliers for paper, printing, etc.) but properly rewarding the people creating the value.
Admittedly, one of the ways we've done this is by mitigating the risk that usually comes with publishing a book (surprisingly, to me at least, as risky and blockbuster-dependent as a Hollywood film) -- xkcd's readers know that merch (and this is one extension of it) is what pays the bills. And there's plenty of them, hopefully more than a few will want this on their bookshelf beside their old Calvin&Hobbes collection (I know I do, that's why I wanted to help this come to fruition).
I Can Has Cheezburger?, Garfield Minus Garfield, Hot Chicks With Douchebags, Suck.com, Indexed, Sleeveface, Passive Aggressive Notes, REAL Ultimate Power
Another well known webcomic which has been released in print form is Megatokyo. In fact, they're up to five volumes now! See: http://www.megagear.com/category_s/67.htm
We had some interesting discussions about how to best do it - jedberg@reddit had one of the cooler ones that involved building your own decoder to pass over the obscured text. In the end, Randy suggested a discrete Copyright-esque position and font that was a simple, elegant solution.
Does the NYT really think that xkcd is "wildly popular among techies the world over for its witty use of programming code in its gags"? I literally winced at that. Are newspapers legally obligated to get it subtly wrong when talking about subjects that I, personally, know about?
(No disrespect to xkcd, and kudos on getting the NY Times placement.)