Today uses the same task storage engine as iCal, Apple Mail and any other application that takes advantage of a new framework in Mac OS X Leopard called CalendarStore. This makes it easy to integrate Today's task functionality with your favorite GTD applications such as OmniFocus or Things.
I'll show you how I'm using OmniFocus along with Today to have an outside view of my OmniFocus tasks.
Open iCal and create a few calendars that will hold your tasks. This is optional, but I have a lot of contexts and they didn't all perfectly fit in my "Work" and "Personal" calendars. For instance, I setup an "Outside World" calendar that has any of my frequently visited places that I've set as contexts.
Open OmniFocus's Preferences window and go to the Sync pane. On the left you'll see your iCal calendars. On the right will be your unsynchronized contexts.
Drag any context that you want to be synced to iCal to the calendar you want it to synchronize to. In my case, I'm only syncing my most important, non-work related tasks over. Usually this is things like errands, bills and phone calls I need to make.
Go to the File menu in OmniFocus and select "Synchronize With iCal." The tasks will automatically be filtered into your Today window's task pane. It will also pass any task that was already in iCal to your OmniFocus inbox so you can keep them organized as well.
A similar workflow is possible in other applications, so if you have a favorite application you're syncing with Today, let me know in the comments!
