While this is a regression, 3.3 definitely puts an increased emphasis on using importlib.import_module() instead of builtins.__import__().  Any reason why import_module() isn't used?

As to the regression, while the current behavior makes more sense, it is contrary to a common idiom when using __import__().  However, given the push away from using __import__(), perhaps it can just stay this way.  Oh backward compatibility...