Unlike the two reviewers before me, I actually had a look at this app. While it has a lot of functionality in reshaping your outlines and the rate at which updates are released is impressive, I do not see how you can rate an outliner with five stars that does not have multiple colums.
In fact there are no columns at all, so no room for dates, dollars or things like "person in charge". I also don't like the user interface of many icons and no text explanation. BTW explanations, there is no online help. FO is in beta and seems quite stable. So I think with improved user interface (but still no columns) this app would deserve four stars if it was free (OmniOutliner puts you down at $30). But that is uncertain as there is no information on future price and the demo runs out June 1.