Apple’s success with the App Store is no secret. 50m+ iPhone and iPod Touch customers have downloaded apps more than 2bn times. More than 85,000 apps and 125,000 app developers compete for a piece of the action.

So it’s no surprise that more and more companies are trying to find ways to replicate the ‘app store‘ model in some fashion. From Twitter to Intel, the model is being embraced.

Inuit, which recently purchased personal finance startup Mint.com for $170m, is getting into the game. The 2010 version of its flagship accounting software, QuickBooks, contains an app store of its own.

The Intuit App Center offers QuickBooks users the ability to purchase premium apps that are designed to enhance and add on to the QuickBooks experience. Apps include Green Snapshot, which provides “recommendations on how to save money by going greener“, and Advantage SmartRoutes, which helps businesses with route planning. The former is developed by Intuit, who will be developing more apps internally, while the latter is developed by a third party.

The App Center is launching with more than 20 apps but this number will likely increase significantly over time. Intuit has its own developer program — the Intuit Partner Platform — which reportedly has 90,000 enrolled developers. Certainly there will be plenty of developers intrigued by the possibility of developing paid apps for the 4m businesses that use QuickBooks.

The question, of course, is whether Intuit will be successful. Apple has been extremely successful with the app store model but that’s not the case for everyone. Several comments on the PC Magazine website hint that some customers may see the App Center as a means to “nickel and dime” QuickBooks users who pay up to $400 for the QuickBooks software. Thus, it appears that Intuit would probably be wise to ensure that the core functionality offered by QuickBooks remains robust. It may also want to consider how to deal with paid apps that overlap with functionality that should probably be a part of the core QuickBooks package.

One thing is for sure: the app store model is only growing in popularity and while not every app store will be a smash hit, smart and nible developers have more opportunity than ever to find a profitable niche. Choose wisely.