Since the documentation for 6.7 is sparse and the exam for 6.0 and 6.5 ends in August.
What should i be studying now?
From what I understand feature have changed from 6.5 to 6.7 - shouldn't that effect the foundation exam questions?
for should i wait?
In my case, I took a required course that is only valid for the 6.5 DCV cert so I am prepping for the 6.5 Exam. Despite this, I am leveraging materials that range from 6.0 through 6.7.
In your case, What does your current environment have? Which version are you prepared to upgrade to? Do you have any limiting factors where it makes sense to go ahead with the 6.0 or 6.5 exam version? All of these questions should play in to your decision.