I use Kate (KDE Advanced Text Editor) for most of my development, including Django. It has both a Python and Django Templates syntax higlighting. I switch to Quanta+ when a significant part of the project involves HTML.
Since it uses Kate's KPart, it's just as good for editing the Python parts, and for the HTML templates i have the whole Quanta+ tools, while still highligting Django-specific tags.
Update 2013: Unfortunately, Quanta+ has been dead for years now, and there's no hope that it will ever be resurrected. Also, there's no other usable HTML editor out there, so it's Kate all the time now.