I wrote and passed the Xen Desktop 3.0 (1Y0-A14) yesterday with a 98%! Overall this was a straight forward exam, no big tricks. There were a few questions where you were told the task that you needed to preform and they listed all the steps to do it and you needed to put those steps in the right order. All the other questions were very short and if you know your stuff then it shouldn’t be too hard an exam.
My advise would be to focus heavily on studying provisioning server because that played in big in the exam that I got.