I found that exam to be very wordy, and while Cisco exams are well known for it to begin with, I found that exam to be very poorly written (many, many typos to the point where I didn't understand a question).
For myself, I started preparing for the CCDA the day I finished off my CCNP, so I pretty much skipped over all the technical chapters and focussed more on the procedural, best-practice material. If you're already a pretty technical Cisco person, anywhere near CCNP-level, I'd say you should spend nearly all of your time on those kinds of sections too.
Be ready for wordy questions. It would be fair game for Cisco to give you an example of work that someone's doing, for example, and ask what stage of the PPDIOO model the work relates to.
While I didn't find much value in CCDA itself (ie: I didn't feel like I had a whole new skillset up my sleeve, as I did after CCNA and CCNP), it leads to CCDP, which is excellent. They changed the curriculum there recently, but last year's ARCH exam was a good challenge, and the Cisco coursebook is probably the best book on network design I've ever read.
CCNP, CCDP, CCIP
Core Network Planner, ISP