Hi there! "Founder" here :)
To answer your questions, David:
Target audience: young-ish, busy, schedule-driven folks like me who have very little time to figure out the nuts and bolts of cooking. I'm deliberately not targeting families because the initial focus is on cooking for oneself, cooking voluntarily as a habit, developing intuition and love for cooking. It's hard to do that once you have mouths to feed.
Why missions? This summer I ran a bunch of experiments (documented at http://mixheatrepeat.com/) to discover what made people cook. One of these was a 1-week game called "Kitchen Quest" (http://kitchenquestgame.tumblr.com) I discovered that the "quest/mission" based format was a big motivator for people. You can read about the experiment results in detail here: http://mixheatrepeat.com/post/95...
Orbital Bootcamp
CMX