This is an absolutely fantastic idea and is really well executed.

What I find to be even greater is that as you run through the thread of comments, zds is responding to feedback and then going back to Codecademy.com to actually incorporate it on the fly.

It's 10 hours since this was first posted and I just read some comments on "you should be able to skip registering until later" and it's already available when you get to Lesson 3.

A great way to listen to and incorporate the right user feedback into your application quickly and effectively.

Really good stuff!