Should black box or white box testing be the emphasis for testers?

Question

Which type of testing would you say should be the emphasis (for testers/QAs), and why?

A quick set of definitions from wikipedia:

Black box testing

Answer 1

White Box Testing equals Software Unit Test. The developer or a development level tester (e.g. another developer) ensures that the code he has written is working properly according to the detailed level requirements before integrating it in the system.

Black Box Testing equals Integration Testing. The tester ensures that the system works according to the requirements on a functional level.

Both test approaches are equally important in my opinion.

A thorough unit test will catch defects in the development stage and not after the software has been integrated into the system. A system level black box test will ensure all software modules behave correctly when integrated together. A unit test in the development stage would not catch these defects since modules are usually developed independent from each other.