Can I extend Jenkins with Jython/Python
Since Jython can produce Java classes I see no reason why this should not work.
Note that you will need to learn at least some things about Java (mostly the platform, not necessarily the language) in order to be able to write plugins for Jenkins.
Is it possible to write Jenkins plugins using Python (via Jython), and if so, where would I get started? I don't know Java (and don't have a real interest in learning it at the moment) so being able to use Python would be nice for me.