This is existing behavior.  The error messages are coming from Distutils doing a byte compile (producing .pyc) on .py files it is installing.  AFAIK, that has always been treated as a warning in all versions of Distutils; changing that behavior now could break the installation of existing packages (yes, I have seen packages, usually tests, that produce these messages).  As is the case with much of Distutils, its exact behavior with regard to byte-compiling has never been documented.   

Note that while pyttsx uses setuptools in its setup.py, even if you edit it to call distutils directly, you still get the same behavior (neither pip nor setuptools nor python3.4 is involved):

curl -O https://pypi.python.org/packages/source/p/pyttsx/pyttsx-1.1.tar.gz
tar -xfz ./pyttsx-1.1.tar.gz
cd ./pyttsx-1.1
python3.3 setup.py install -v
[...]
copying build/lib/pyttsx/voice.py -> /Library/Frameworks/Python.framework/Versions/3.3/lib/python3.3/site-packages/pyttsx
byte-compiling /Library/Frameworks/Python.framework/Versions/3.3/lib/python3.3/site-packages/pyttsx/__init__.py to __init__.cpython-33.pyc
byte-compiling /Library/Frameworks/Python.framework/Versions/3.3/lib/python3.3/site-packages/pyttsx/driver.py to driver.cpython-33.pyc
  File "/Library/Frameworks/Python.framework/Versions/3.3/lib/python3.3/site-packages/pyttsx/driver.py", line 105
    except Exception, e:
                    ^
SyntaxError: invalid syntax
byte-compiling /Library/Frameworks/Python.framework/Versions/3.3/lib/python3.3/site-packages/pyttsx/voice.py to voice.cpython-33.pyc
running install_egg_info
Removing /Library/Frameworks/Python.framework/Versions/3.3/lib/python3.3/site-packages/pyttsx-1.1-py3.3.egg-info
Writing /Library/Frameworks/Python.framework/Versions/3.3/lib/python3.3/site-packages/pyttsx-1.1-py3.3.egg-info
$ echo $?
0