Biswajit Sarkar has written another java.net article about styles, painters & themes. Its more up to date with the current style architecture in LWUIT than other articles covering the subject.
His article also covers some other new LWUIT features such as tables.
On an unrelated note Ofir got tasked last week with getting a LWUIT application to run efficiently on Symbian OS 8. He benchmarked the application and discovered that the cause of performance issues is the existence of an alpha channel in the images. The performance difference he showed us was staggering!
We always new bitmap fonts were slower on such devices (an image with an alpha channel) but it seems that even simpler transparency (without translucency) might make a huge difference.