First of all, the design looks great! And I love the "Labs" moniker much more than cookbook.
But I am still ambivalent about the concept:
- There's a very large overlap on content between the wiki and the cookbook. I see no clear way to explain what must go to the wiki and what must go to the cookbook.
- Openness: it's unclear if the recipes will be only added by TTN, or if it will be possible for everyone to add them. Both options have issues: the former feels too closed and restrictive; the latter feels like a wiki with a different name.
- Centralization: while I agree is good to have a neatly organized central documentation, it is unclear what will happen with all the HOWTOs that are already out there on the internet, mostly on github repos. Do they 'have to' be copied over to this one? Or can a recipe be just a nice picture, title and an external link? The latter feels to me like a good balance acting as centralized index, but decentralized content. It also removes some of the concerns about this being just a wiki with another name.
I didn't really get the "Groups" thing. Could you clarify what would be the advantage of any given user that motivates him/her to join a group?
Cheers!
Gonzalo