The final cover is as follows:
Henry Kleynhans, newish NetBeans Platform developer in South Africa, the first/only person who has seen the actual PDF so far, other than myself and Packt, told me this about it on Twitter: "I really like it. The way in which concepts are incrementally introduced is very intuitive. Going through Lookup now..."
And that's, I believe, the strength of the book: its incremental approach. Often you're first told how to do something the wrong way, followed by an explanation of the alternative/better/right way to do the same thing. I think that especially the Lookup and Nodes chapters are very good in that respect.
I think the book continues to have some problems, but that it really works in giving a global overview of the main APIs in the context of a specific application. Looking forward to other comments from readers once the book is actually published. Thanks to the many translators and reviewers, you'll find that you've been mentioned and thanked in the book!
Now, let's start working on the next book. Part of the profits from this book will be dedicated by Jürgen to the writing of the next one. What should the book contain and who'd like to be involved in writing it?