Just got back from taking the 70-551 exam (71-551 in beta).
3 sections, 30 questions each (for a total of 90 questions). Each section correlates to the Official Exam Objectives published by Microsoft. At the end of 90 questions (at around 87 actually), I was exhausted and could not wait to be done. Luckily, I felt I did pretty well on the last section so did not have to spend much time reviewing it and could just end it. The whole test took roughly 2 1/4 hours (although I had 3 to complete it if I wanted).
Each section allowed 60 minutes to complete. No going back once you've completed a question although the usual Previous/Next is allowed within a section, and a review at the end of each section.
I found the test hard in some places and easier in others. The first section (on .NET Framework) I may have barely gotten 60%. The next section, on web development, was also tough but I did slightly better, say 70%. And the final section, on design and development in general, I did better still at 80%-90%.
So who knows if I passed. I don't. The results come in 8 weeks apparently.
Anyways, on to the Windows test next Sunday. Don't forget to visit my 70-551 Wiki. I am starting one for the Windows exam 70-552 as well.
Disclaimer The opinions expressed herein are my own personal opinions and do not represent my employer's view in any way.