Now that the VCP on vSphere 4 exam is finally live, VMware have released a number of official resources to help those who want to obtain what will quickly become the new "industry standard" virtualization certification.
The exam blueprint is THE document to base all your study on as it tells you exactly what you get tested on, if you're studying something that's not in the blueprint you're wasting your time. VMware also have an official mock exam, to help you get used to the question format and style. You'll find both of these under the VCP pages on the VMware website:
So the blueprint will tell you what you need to know, and the official documentation is the best material to study from as the questions are written from the documents you will find at:
There are also a number of unofficial resources which can be very useful too. Fellow blogger Simon Long has some excellent practice questions and a version of the exam blueprint with hyperlinks taking you directly to study resources:
Forbes Guthrie is well-known for producing a leaflet-style reference card for the VI3 exam, he's produced a new version specifically for the vSphere 4 exam:
Update - 1st December 2009
Global Knowledge also offer a VCP4 Exam Preparation Workshop, written by me:
I've also recently been made aware of a new, unofficial, comprehensive study guide:
Update - 23rd July 2010
Links updated to reflect current exam blueprint and vSphere documentation.