Given the somewhat disjointed style used in README files, it's not 100% clear that this new note about deprecation warnings applies *only* to running numpy.test. Could we make it something like

Starting in NumPy 1.7, any test which triggers a deprecation warning will automatically fail, so the -Wd command-line option is no longer necessary for running the test suite.

(Also, does this change really apply only to deprecation warnings, or to all warnings in general?)