Three short years after my post about the need for a central software repository in a mainstream operating system, Apple has gone ahead and done it. The huge success of the iOS App Store model has prompted Apple to create a similar App Store for its upcoming version of Mac OS X.

As an iPhone user for the last three years, I've had mixed feelings about the App Store model of software distribution. Or rather, with Apple's implementation of it. On one hand, the approval process that an application has to go through before it makes its way into the Store ensures a certain baseline level of quality for users, at least in theory. On the other hand, it also means that the decision on whether or not you can install a third-party application on your device lies in the hands of one entity -- and it's not you, it's Apple.

One of the key distinctions between Apple's App Store implementation on iOS versus Mac OS X is that "jailbreaking" aside, the App Store on iOS is your one-and-only source of third-party applications, whereas on OS X, the App Store is just one of the ways to download and install third-party applications. This is important, because it means that Mac users get all of the benefits of the App Store model (such as centralized searching and billing, automatic updates, quality control, etc.)  without any of the restrictions that come with the iOS implementation. This is great for independent developers and end-users. And Apple gets its cut every time an application is sold. Everyone wins.

Has Microsoft realized this yet? How long before something like this shows up on Windows?