Ken Case, writing at the OmniGroup Blog:
For example, we think there is opportunity to improve the way OmniFocus schedules tasks. Each task currently has two dates related to scheduling. Its due date is the date it should be completed by, while its defer date is the date it becomes available. (In OmniPlan, where tasks are scheduled in much more detail, we would call these the start after and end before constraints.) Both of these dates are important, but they leave an important question unanswered: when do you actually plan to do the task? (What is its “do” date?) Some people end up using (and moving) the due date to schedule their tasks, while others use the defer date. But neither of those fields are truly ideal for scheduling. We think adding a scheduled date would improve the way tasks are scheduled.
This is pretty exciting for to-do app nerds. The battle rages on about “do” or start dates in Todoist, and is an often-cited friction point for users of that service. (It looks like they’re working on it.) OmniFocus is better than Todoist, in this regard, but far from perfect. (I maddeningly use flags and defer dates to narrow my focus.) Another level of filtering would help immensely, and would be interesting if the feature is not just another version of a start date.