One of the big areas on the exam that could be of concern are the topics that you might not use everyday or have used at all. This exam will most likely contain quite a few SAF questions. SAF is a big area I believe Cisco Systems is trying to push. It would be a good idea to study all aspects of SAF. The areas of focus should probably be how to configure it. The configuration should include basic and basic troubleshooting. The nice thing about SAF is that it is pretty straight forward to configure and troubleshoot. You should also know how the Communications Manager uses SAF to make call routing choices. Study of these areas should provide enough information to perform well if you encounter SAF during this exam.
Another major subject that is likely to appear will include Mobility. Mobility can include extension or device mobility. While Mobility can cover all aspects the technology, the same rules should apply to your exam preparation. You should be able to configure the basics as well as answer basic questions on Mobility.
The last area that you should be aware of is the Cisco style of questions. You will need to carefully examine the question to best decide how to answer it. Some of the questions will probably look very close with only a few words that will totally change the answer. This area should be in the exam takers mind when taking any Cisco exam.