Maybe it's weird... but I really like watching other people writing a project (Like in the Ludum Dare), I like to see how they tackle the design, how they work, what cool tricks they use, etc.
You can even interact with them via chat, and not only help but also ask questions about what they are doing... is great for people who are still learning.
Although many people seem to do fine for the Ludum Dare.
It was completely streamed live and was really enjoyable, they'd work and chat to the watchers at the same time, answer any questions and give advice on what they were currently doing. Rather annoyingly it worked really well but I haven't seen anyone repeat anything similar since.
I think we can all agree that when it comes to programming the _best_ way to learn it is to actually program.
But, even Programming has to be taught. Among the many ways to learn programming, I think the best approach is to demonstrate how a good progammer programs and explain the thought process.
Also - I haven't actually watched the screencast, but looking at the text the virtualenv setup seems very wrong.
I do wish knowing GML was good for something somewhere else though. Or that it used another language like Python for its scripting.
I can't copy-paste code from a video.
Searching is orders of magnitude slower than just pressing "Page Up"/"Page Down". This is particularly important when I just want to take a glance and figure out if the text/video is of any interest.
I have to adapt myself to the speed of the video, and maybe most importantly, I have to swallow all the non-relevant parts (such as moving windows, launching commands, typing, etc.).
It takes me so much more effort (and patience) to watch a video instead of reading an equivalent text, that I almost never do so (khan academy being the exception).
As Sartre said, Hell is watching other people use a computer.
I wrote the same article and demo a month ago, albiet a more comprehensive and complete approach using Mezzanine (a Django based CMS). The article focuses on how most of the features needed for something like this come out of the box with Mezzanine:
I really like some aspects of Mezzanine, and I've used it on a couple of projects with success. But I don't like Grappelli much, I prefer django-admintools so for this reason alone I prefer FeinCMS or Ella.
Never understood why Grappelli removes the button click from admin actions!
myself, i wrote a HN clone one afternoon (when HN was down for several hours) using flask. since i'm the only user, i feed it with twitter. what i did was set up a twitter account - @hacktweetnews - and have it follow most of the top twitter users from the HN community  and then score it reddit-like. no votes aside from what people post as duplicates, no comments - so it definitely lacks the full features you have, but then again it's just me. however, like your django example, it was super easy to set up in a framework. yours is definitely far more feature-filled!
https://github.com/wilfra/theplayr (live site: http://theplayr.com)
This screencast looks awesome! Okay, now to your questions:
First, the screencast for creating a HN/Reddit clone is a tutorial. It's a good place to start when developing in Django, or as a reinforcement for the existing tutorial.
Second, Two Scoops of Django came out first because we (me and Audrey Roy) wrote it first. Arun Ravindran, who is making this tutorial, is a separate person and completely unaffiliated with us.
Not to mention getting the audience, but that's not really a technical problem.