I had to install OpenStack using devstack infrastructure for experiements with open vSwitch, and found this in the logs:
/usr/lib/python2.7/site-packages/setuptools/dist.py:298: UserWarning: The version specified ('2014.2.2.dev5.gb329598') is an invalid version, this may not work as expected with newer versions of setuptools, pip, and PyPI. Please see PEP 440 for more details.
I googled and found PEP440, but I wonder how serious is this warning?
As an end user, this shouldn't be a serious concern for you, it just means that, since the version number specified doesn't agree with the rules for python package versions, that the python packaging system cannot reliably discern which other versions of this package are before or after it.
In particular, its not specified if 2014.2.2.dev5.g... should come before or after 2014.2.2.dev5, since the rules don't say anything about what g is supposed to mean.
this is not likely to affect you too much; since either are going to be dev releases; and both strictly are between 2014.2.1 and 2014.2.2