Introducing Python
It's really all about schedules.  To me the break should be with a specific project.  If you decide your direction is Django then start new projects with that.  Before you start a new project with a new language/framework, either make sure that you have scheduled time to get up to speed in this new direction, or get up to speed before using on new projects.
I would avoid going with a tool of the month.  Make sure you want it to be your direction and commit some time/resources to learning enough to make a good decision.
The company I used to work with has two developers working fulltime, and a handful of freelancers. They're in the process of hiring a new lead developer to try to bring order and management to the development.
But, currently, one of the developers has seen the light of Django (the company has only developed in PHP to date) while the other developer is concerned that introducing a new language (Python) is a bad idea right now.
How should they approach introducing this new technology? Obviously with only one of the developers actually knowing Python, there will be no redundancy when that dev is away or leaves the company.
Should they bother to introduce Python, or should they look for PHP-only solutions until such a time when the team actually have more than one Pythonion? Without a team leader, the decisions are having to fall to them.