As Jonathan Zittrain blogs, the iPhone 3G still leaves free (as in speech) software lovers a lot to worry about, but the App Store implementation in particular gives me hope that the Ubuntu (really, Debian) model of centralized repositories has legs.

I’ve been a happy Ubuntu user now since the first Warty Warthog release, but strangely enough one of the things some people have the hardest time getting used to is Synaptic, which is the program that Ubuntu uses to download and install most applications.

Unlike Windows or Mac, for example, in Ubuntu you rarely download an application from your web browser or buy a program on a CD. Instead you open up Synaptic, which lets you browse thousands of programs all hosted on a central, often university-run server, with backups distributed across the globe at other volunteer servers.

You can just check off all the applications you might want – say, word processor AbiWord and paint program GIMP – and then Ubuntu downloads and installs the programs, occasionally prompting you for administrator access rights to make sure you want to install it and it’s not spyware, as well as to get any configuration information it might need.

It’s a big shift from what we’re used to: Hundreds of different, unvetted online sources and a few expensive boxed applications are all traded for a single online storefront, where nothing is charged for. That store then handles any future patches and upgrades, checking occasionally to see what’s new and what you need to keep your system safe.

And now, Apple is bringing this centralized repository system to the masses with the iPhone App Store. Apple strikes a good balance of providing great free content (Pandora, Remote) alongside easily paid for commercial content. Could this be a model for the future of Ubuntu and other Debian repositories?

While many in the Open Source Community abhor closed-source software, many more are fine with it, and giving repository maintainers a cut gives them more incentive to properly maintain their software archives. And that proper maintenance isn’t an entirely academic discussion: As University of Arizona researchers discovered, it’s very easy to seed these volunteer repositories with malware one way or another (more related discussion on Slashdot.

Even without closed source software, a package manager tightly integrated with a simply payment scheme could be huge boon to Canonical and their various repository hosting partners. Imagine, logging into Synaptic and not only see downloadable software but also the option to buy support in 15 minute increments straight from Ubuntu-maintainer Canonical or licensed third parties.

Canonical has a way to make money off fickle home users, while non-geeks get an easy way to work through their setup problems. That concept could be expanded into a wide array of services, which give greater or lesser access to the host computer depending on what needs to be done or trained.

Ubuntu’s had tremendous success in the free software world, and the iPhone App Store validates much of the package management techniques Canonical uses. Now it’s time to polish that a little bit and give Ubuntu some real competitive edge.

Edit:I took out the tiny picture of the iPhone store because it looked weird.