Just came out an hour ago. Preparation-wise, I suppose I did about what most other folks taking this exam did: studying the 'SCWCD Exam Kit' and purchasing and using the related JWebPlus exam simulator. Both resources are very useful in preparing for this exam. Of course, JavaRanch is an incredible resource. Thank you all.
Thanks Iftikhar Ara. I don't know the exact number of questions I was asked on DD elements, but I was definitely asked a number (I'm guessing 6). And these questions were spread over several sections, so I can't give you one percentage for the section. It did seem like much of the exam required pure memorization of material (method names, which classes implemented which feature,etc.), but there were a few questions that required a little more understanding. Again, I'd really recommend 'SCWCD Exam Study Kit' to learn the material and their JWebPlus mock exam to guage your progress.