After putting it off for six months, I finally took - and passed - 70-431 yesterday. I know, I'm probably one of the last ones on board, but I'm kind of a geek and I don't want to sit for an exam until I'm really ready. I've failed two MS exams and after each failure I was bummed out for a while. In fact, when I failed 70-228 (the SQL 2000 admin/maint exam), I waited for an entire year before I retook it. But enough about my hangups...
I can't disclose much for fear of violating the NDA, but I can say that 70-431 was unlike any other cert exam I've taken. There was a section of standard Q&A format, and there were some really tough questions - two of which I answered with what can only be called an educated guess. The second part was a simulation of several tasks in a GUI simulator. This to me was the toughest part, because I didn't (and still don't) know how exactly these are scored. The simulator is intimidating in that the possible answers aren't laid out for you; it's up to you to work through the problems presented and find the solution yourself.
For those who would consider this exam, I can tell you what worked for me. The SQL Server 2005 Implementation and Maintenace book by Microsoft Press was the primary text I used to prepare for this exam. It takes you on a broad (but not deep) trip through SQL Server 2005 and its core features, and for me this was very useful in preparing for the Q&A portion of this test. As good as the book was, the electronic test simulator included was of little help; the questions and answers were badly worded, often misspelled, and even more ambiguous than what you would expect from standardized tests. As far as the simulations, the best thing to do to prepare is to get to know the GUI of the product. Don't just learn the T-SQL to accomplish all of your tasks - although this is helpful and necessary, you should also be prepared to demonstrate your knowledge about using the interface. For the simulations, a recent certification prep course from Chris Ford, a local (Dallas area) SQL Server consultant and trainer, helped to expose me to some of the functions of SQL Server with which I had little experience.
Professional certifications have taken a hit lately as a relevant measure of experience and knowledge, and with good reason. Old fashioned Q&A tests simply measure one's ability to answer questions when all of the possible answers are presented to you; these tests do not measure one's problem solving skills, and they allow for unscrupulous test takers to simply memorize questions and answers ahead of time. I like what Microsoft in adding simulations to the exams, which require the test taker to have at least some knowledge and problem solving ability with the product. I think this change increases the difficulty - and therefore the value - of the certification.