For easy Genshi templating: http://packages.python.org/Flask-Genshi/ Thanks Armin for help designing the API and for the logo!
New version 0.3, adds support for per-method filter callbacks. <http://packages.python.org/Flask-Genshi/#flaskext.genshi.Genshi.filter>
New version 0.2; adds support for js and css templates. I found myself needing url_for in my javascript.