Yeah, it is a result of the fix for issue11591 (changeset a364719e400a).  Incidentally, the decision was made to forgo writing a testcase in favor of proof by inspection :-)

There are also other consequences of that change:

   ./python.exe -S
   Python 3.4.0a0 (default:08c215115842, Dec 30 2012, 09:54:54) 
   [GCC 4.2.1 Compatible Apple Clang 4.1 ((tags/Apple/clang-421.11.65))] on darwin
   >>> import site
   >>> quit()
   Traceback (most recent call last):
     File "<stdin>", line 1, in <module>
   NameError: name 'quit' is not defined
   >>> ^D

'quit' not being defined in this case is a regression.

ISTM the original change was meant to only prevent sys.path from being altered, but it is preventing a bunch of other things (USER_BASE, USER_SITE, quit, ...) from being initialized as well.