Perhaps OmniFocus' integration with iCal would be a bit clearer if we did a better job of explaining two things:
In OmniFocus, the "Start" Date is really a "Defer Until" date: it's a way of taking something off your lists until that date, it's not intended to be the exact moment that work is scheduled to begin. (For that sort of schedule-based planning, you might want to check out
OmniPlan.)
But perhaps more importantly, the goal of synchronizing with iCal is not to synchronize with iCal itself: the real purpose is to synchronize with OS X's only built-in task database. (We mention "iCal" because that was the only built-in Tiger application which could access that task database.)
The value of synchronizing with the system's task database is so that you can synchronize those tasks with other applications or devices which synchronize with OS X, such as BlackBerry handsets, Palm OS devices, Windows Mobile devices, and many mobile phones. (If OS X doesn't have built-in support for synchronizing tasks to your mobile device, you might want to check out mark/space's
Missing Sync products.)
Of course, that sort of synchronization isn't nearly as nice as putting OmniFocus itself in your pocket, which is what we're doing for the
iPhone and iPod Touch versions of OmniFocus.