Elegant simplicity
2Do is nice but fairly complex, unintuitive, and doesnt provide the option to present your tasks in iCal. Priorities does it all, and far more intuitively. The high point: the option to see your tasks in iCal. You always get your big picture at a glance, without flipping between apps. Clean, simple, but fully-featured. Priorities really is a gem.
Checkendon about
Priorities, v2.3.2