We still feel upgrade pricing is important for customers purchasing serious productivity software, since the initial value received from purchasing an app like OmniGraffle or OmniPlan is much different from the incremental value of upgrading that app from version 5.0 to version 6.0. So long as we continue to sell our apps through the Mac App Store, we are not allowed to distribute updates through other channels to apps which were purchased from the App Store. My apologies: I’m afraid we will not be able to offer upgrade pricing to our Mac App Store customers after all. Update: While we’re unable to offer upgrade discounts for Standard editions of our apps through the Mac App Store, we’re hopeful that Apple will continue to approve upgrade discounts for Pro in-app purchases for customers who have previously purchased our apps through the Mac App Store, just like they’ve already approved for the upgrade discounts we offer for the Pro edition of OmniGraffle 6.
Update: We’ve found a way to offer upgrade discounts and trials on the Mac App Store! Starting with OmniGraffle 7.