[pecko]

There's one think iCal can do which OF can't on both Mac and iPhone... Alarms. With this native to both iPhone and Mac you don't need the iCal app open to have an alarm remind you of your next task.

Also it would be good to plan a particular day of various tasks in iCal based on the due date and time allocated in OF.

Unfortunately iCal's tasks don't handle time and only allocates a "day" due date.