This is another amazing gem from Nic and the team at Zen. I already have the Zen flowchart and maps. Initially I was skeptical of the minimal approach but now get what they are about.
Zen wireframes is also similar. The idea is not to replace your designer but to do simple prototypes yourself if the designer is unavailable, at a really fast pace. If you follow agile principles, you will love Zen.
Wonder what they will come up with next :)
All the best:)