I have been waiting for confirmation from the VMware Certification Team regarding this and it came in today.
For those of you who remember, when the track was released there were a number of people already in the process who wanted to upgrade to the new track. The assurance back then was that people already in the track would receive a discount on the new exams.
After exchanging emails back and forth with Jon Hall and the Certification team, asking about this discount, I received this in my inbox today.
If you have passed the VCE310 exam (but have not yet passed the VCD310 exam) and are a VCP4:
Register for the VCAP4-DCA exam at a discounted rate. Become one of the first VCAP4-DCA certified professionals, and fulfill one of the pre-requisites for the VCDX4 certification.
Sign up to register: www.vmware.com/go/vcap
Our records indicate that you have successfully passed the Enterprise Administration Exam. Your voucher for a 50% discount on the VCAP4-DCA Exam is:
Expires: March 31, 2011
This voucher is good for one use only. It cannot be combined with any other promotions. Voucher expirations cannot be extended. You must be a VCP4 in order to register for the VCAP4-DCA Exam.
VCAP4-DCD Exam vouchers will be distributed to eligible candidates at a later time.
If you have not received notification I would suggest that you contact the Certification team to see if you are eligible.