Advantages for shop owners:

• You have option to update commercial extensions directly from Magento
• There will be no problem with tracking bought extensions, downloading on eshops and complicated implementation
• Before you buy a package you will see the update history and decide if the extension is maintained

  Advantages for developers:

• You do not need to have e-shop to sell your extension
• Your customers have not to be afraid of non updated extensions
• Sell the extension as service annually not just once