I just want to pass along some positive comments about JFreeChart.
I am sure you get lots of questions and complaints from the various users around the net (especially newbies), but you may not hear much from those that have downloaded and used JFreeChart successfully with very little trouble.
I am one of the latter.
I started using JFreeChart about 11 months ago for various projects with clients (I am an independent consultant).

The coding style is clean, the code works, and documentation is pretty good. The bottom line is that your library has given me a big leg up on several projects where I needed a charting library. I believe I did a fairly thorough search last year for charting libraries and I am very happy that I went with JFreeChart.
I bought the Developer's guide. It and the demo code were an excellent value.
Now that I have several months of experience with it, I am now starting to push it toward more advanced features.
Thanks for all your efforts. JFreeChart Rocks!
Best regards,
Stu