Passed the 70-284 exam today! It was a strange test. Half of the exam was all about installation issues, and the other half was about routing/connections issues. I thought I would be answering more daily Exchange tasks questions, but I found myself using more 70-291 knowledge, memory of Exchange defaults, and little tidbits of installtion facts that I'm glad I retained. Passed with only 790, but I'll take it.
Used MOC 2400 book, Microsoft E-Learning, Measure Up Practice Exams, and Exchange Server at work

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I also got very nervous at the beginning of the exam when I saw that their were only 30 questions!!