Today was a big day for me, I finally got to take the VCAP4-DCA exam for vSphere 4 - this was the third time I had been scheduled to take the exam and this time I didn't have to re-schedule it - ahh, the joys of being a busy man! It goes without saying that I can only give out so much information on the exam, I definitely don't want to violate any non-disclosure agreement after going through 3.5 hours of work and a lot of preparation!
So, on to what I can say... It's a tough exam, fair, but tough. You get given a really wide variety of tasks to carry out, some of them relatively straightforward things that any VCP would know how to do, other tasks were very in-depth and quite complex. I used a variety of different administrative interfaces - this is not an exam that you can do with the vSphere Client alone - you WILL need to know how to use the Service Console and vSphere Management Assistant, and you WILL need to do some work in vSphere PowerCLI too.
There were a number of tasks that I was asked to carry out that are things I've never had to do before in 5 years of working in-depth with ESX/ESXi and vCenter Server, things that I've never been asked in class or in discussions with customers. I did have a good read through the VCAP-DCA exam blueprint when I came out of the exam just to make sure VMware were justified in asking me to carry out some of these tasks, and I can confirm that they WERE!! You won't get asked to do literally everything in the blueprint document, you get roughly 40 tasks to perform on the day, but the tasks in your exam will be a subset of what's in the blueprint so be prepared to do anything that's in the document.
In terms of preparation, get the blueprint, build a lab, and practice. And just when you think you're ready, practice some more!! I'm sure you're waiting for a list of what resources I used to prepare, or would recommend you take a look at - you really need to focus on troubleshooting, performance, automation and security:
Official advanced-level vSphere courses
Video-based training from TrainSignal
Study guides from people such as Ed Grigson and Sean Crookston
This is definitely a certification that sorts out the men from the boys, puts hairs on your chest, helps you to earn your stripes as a vSphere administrator, and plenty of other cliches. I'm now waiting to get my results in about 2 weeks time, best of luck to you if you're taking yours any time soon...