Apple finally has added a To Do List to the iPhone. Reminders Sync with Microsoft Outlook Tasks. Before this update, Apple users had to use a 3rd Party App like iMEXCHANGE to do this. When you setup an Exchange Account on the iPhone just check reminders to sync your task list. If you upgrade to iOS 5 it will automatically setup the sync.
Biggest Gripe: Apple still does not use Categories. In Outlook Tasks, I have a Category called Call Back. These are the People I need to call back. That Category will not sync over to the iPhone so I have no way to sort my To Do List, which is pretty long.
Legal Specific: If you have a legal specific PMS like Amicus or TimeMatters, your To Do Lists in these programs will now sync to your iPhone via Outlook.