Hints have appeared suggesting that interpolation will be deprecated at some point in python 3, e.g. from this article: http://docs.python.org/dev/py3k/whatsne

Hints have appeared suggesting that interpolation will be deprecated at some point in python 3, e.g. from this article: http://docs.python.org/dev/py3k/whatsnew/3.0.html#changes-already-present-in-python-2-6 http://docs.python.org/dev/py3k/whatsnew/3.0.html#changes-al... PEP 3101: Advanced String Formatting. [...] The plan is to eventually make this the only API for string formatting, and to start deprecating the % operator in Python 3.1. As far as I know, interpolation is not actually deprecated yet though.