We've had a lot of support for our online, free version of Maven: The Definitive Guide, and I think that we've created a good introduction and reference for both new and veteran Maven users. In my opinion, we're about half way to the point of creating a lasting reference for the next decade. Personally, I'd like to see: more examples in the intro portion of the book, and more details in the reference part of the book. I'd like to see a whole section devoted to the internals of Maven and the process of developing Maven. Additionally, I think the community deserves a closer look at some of the unepxected uses of Maven. I could easily see this book growing another 500 pages or being split into two, and I'd also like to see us supplement this reference with other books in the near future.
If you use our free, online reference, I'm going to take the publishing of the print book as my opportunity to suggest that you purchase a copy. This isn't in the spirit of a public radio drive, nor am I trying to position the book as some sort of charity work. I'm asking you to purchase the book (for a little more than $20) as a statement to publishers that Maven matters. I'm convinced it does, and surprising our publisher with some strong numbers will help the community by convincing other publishers that Maven matters.
I'm also making the case because I'm convinced that the world needs more free books in the style of the Subversion book. The Subversion book had strong sales despite the fact that it was freely available online. Maven is just as pervasive as Subversion within the subcategory of Java. I am convinced that free books make more sense for authors, publishers, and consumers, and I have made it something of a personal goal to convince authors to write free. If you like reading free, then help us write more free.
If you like what you see, support it and buy it.