I have used many To Do List managers and currently use Daylite to manage contacts and an action list. But, OmniFocus is better at managing To Do than any other program I have tried. However, because Daylite integrates contact management with a related action list, I am committed to Daylite.

If OmniFocus had a contact management link to address book, I sure I would move to OmniFocus. The OmniFocus link with the iPhone is really fantastic!