Last year a survey was conducted on python 2 and 3 usage.

It sparkled interesting discussions on HN: https://news.ycombinator.com/item?id=6990481 "Python 2.x vs 3.x use survey" https://news.ycombinator.com/item?id=7005711 " Python 2.x vs. 3.x survey results"

Here is the 2014 edition, slightly updated (from 9 to 11 questions). It should not take you more than 1 minute to fill. I would be pleased if you took that time.

The results will be published around the end of the year.