When forecast is selected, the left column gains a calendar showing the next 30 days. A number on each calendar day indicates how many actions are due. Clicking any given date populates a middle column with your list of actions and any events that appear on your iCloud or Google calendar. You can also shift click a date range on the sidebar calendar to see multiple dates in series. For as simple and even obvious as the forecast feature may sound, few other products so elegantly and succinctly marry "What is on my schedule?" with "What must I accomplish?"
Each project can be assigned a review interval--a repeating schedule you set to step back and look over what you've completed and what comes next. When a project's review date arrives, OmniFocus adds the project to the review perspective in the left sidebar. Click the project name to see a compact list of its constituent actions. Revise as necessary and click a "mark reviewed" button to tuck it away. Reviewing your projects is the kind of task that easily gets pushed aside day after day. This approach takes the question of when to review out of your headspace and makes performing the actual review less onerous than it may otherwise be.
Owners of OmniFocus Pro (a standard version is available for $40) gain the ability to create custom perspectives and access to a robust AppleScript library for automating and integrating with other software on the Mac. They also get the ability to temporarily filter from view all but the selected projects.
For as thoughtfully designed as OmniFocus is, some time and effort is required to understand and take advantage of its deep feature set. The Omni Group has responded with excellent documentation. They've wisely foregone Apple's slow and cumbersome on-screen help and created their own. The articles are well organized, thoughtfully composed, and liberally illustrated.
OmniFocus Pro 2.0.2 is at the top of its class. Unless you've really got to have that AppleScript support, the basic version is sure to serve you well. If $40 still seems a bit dear for a task manager, download the trial version. You'll find that the design, capabilities, and documentation make it a very good value.
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