Watch out!

This vendor practices the now all too frequent "buy this high priced version now, and in N months Im going to remove it from the App Store and replace it with blah v2, with a few cosmetic differences, and have you sucker pay for the new version in full, as opposed to pay for an upgrade."
Happened with Omni outliner, and now with Omnigraffle.

Ohm62 about OmniOutliner 2