Disagree. They're nothing about that combination that is special. It should just as easily have been built using, say, Jinja templates and SQL Alchemy ORM.
Saying, "Oh, I could do that with X" is a bullshit statement. You could build an Django-like admin in Fortran.
Yes, you can hack together an admin tool in any templating system, using any ORM, or even raw SQL if you like. It's all just CRUD operations, and provided sufficient/consistent abstraction you can make it work, for your own project, without any troubles. You could, with sufficient work, even create an admin as simple as the register command.
This is the power the ecosystem at play though. When I snag a Django app to add to me project, it comes with an admin. I don't have to cobble one together.
I can replace the Django admin with an api-compatible alternative like Grappelli or Suit, and 98% of all the applications out there for Django will go right on working.
So the admin is not a killer app (per se) but is an example of how Django itself IS a killer app, because the admin is powered by it, and the community enabled by it.
The admin depends on uniform URL conventions driven by the framework and the URL reversion mechanism to get object URLs.
The CRUD DB functionality depends on the models being compatiable with the Django ORM interface, as well as the forms and the interations between the ORM and forms which allows for things like ModelForms.
The admin has its own set of important template tags to render information depending on the context, and that allows for consisten overriding and enhancing of functionality.
The imporant thing is that, even though all those components are decoupled, they were made in mind to interact flawlessly, and share idioms and interfaces that allow them to work together in ways that that more decoupled frameworks do not.
Finally, while there is nothing special about each component per se, most people seriously exaggerate the shortcomings of each, and there is no component in Django that is plainly bad, something that I have personally seen in pretty much every other framework I have worked with. Consistency is important.
I haven't used it, but looking at the quickstart, you gain a lot of flexibility in exchange for a bit of boilerplate. As I haven't done any Django in a long time, I cannot comment on how complete it is, but it shows that you can absolutely achieve this kind of functionality in a framework with a tiny core.
