The samples on which the above tutorials are based were written by some of the undisputed heros of the NetBeans Platform—Jaroslav Tulach wrote the HTML Editor, Tim Boudreau the Paint Application, and Rich Unger the Feed Reader. So, you are in good hands! Now these samples can also be built in 6.0, if you use the tutorials above. Best to follow them in the above sequence, because they increase in complexity. The differences between 5.5 and 6.0, in relation to these tutorials, is minor. However, the screenshots have been fixed (many places where there are small u.i. tweaks in 6.0) and, especially in the case of the Feed Reader tutorial, a lot of explanatory text has been added and some restructuring has been done.
All three of the above are in some kind of 'draft' state, although they should definitely provide the promised result (i.e., the code should be solid). The titles might change by the time 6.0 is released, but the URL to the tutorials should remain the same. Further explanatory texts need to be added, especially in the Feed Reader tutorial. Any comments are welcome, use the Feedback links at the end of each of the tutorials.