I don't think I am violating the multi-paged pre-exam NDA by offering this tip after sitting for 70-236 this morning: know they powershell syntax and commandlets. Easily 75%+ of my test involved trying to choose which syntax I should use to perform a configuration related task in Exchange 2007. I have heard there was some powershell on the exam. I even looked over the "skills being measured." This is the only item among 20 or so: "Implement bulk management of mail-enabled objects." Hmmm. I was not happy.
I am a GUI-lover! I have never been a CLI junkie ... I will do 99% of my tasks from the Exchange Management Console unless bulk modification activities are required. However, Microsoft has decided I can only be a pro if I know the command line ....