A good tutorial, but it was missing any mention of blueprints, which are essential to building a Flask site larger than a few endpoints. Blueprints also allow you to reuse components across multiple apps, or as releasing a set of endpoints as open source libraries that can be easily plugged into other apps.
Great, looking forward to it. I love Flask, and am working on a backend site built on top of it (http://woventheapp.com) -- the more people we can get knowledgeable about it, the better!
Edit: adding a link to Blueprints in the Flask docs: http://flask.pocoo.org/docs/blueprints/