Update: Unfortunately this is not possible with recent versions of OmniFocus with Mountain Lion. You can read more about it here. If you're using an older version of OmniFocus and haven't upgraded to Mountain Lion, you might be able to still get this to work.
If you're running an older version of OmniFucus and OS X 10.6 (Snow Leopard) or 10.7 (Lion):
Yes you can. OmniFocus can sync with iCal, and once the data is in iCal it will be available to Blotter.
From OmniFocus' manual:
- Choose OmniFocus ▸ Preferences, then click the iCal icon.
- Select the Unsynchronized group in the Calendar list; all of the contexts you’re not synchronizing appear in the Contexts list.
- Drag context names into the calendar name you’d like to synchronize them with. For instance, if you drag your “errands” context to your “Home” calendar, any actions assigned to your errands context will get corresponding to-do items in your Home calendar in iCal.
- From the File menu choose Synchronize with iCal. For each context that you dragged into a calendar, its actions are synchronized to iCal.
- Whenever you like, choose Synchronize with iCal to bring iCal and Omni- Focus back in sync. New OmniFocus actions in synchronized contexts are copied to the associated calendars in iCal. New iCal to-dos in synchronized calendars are copied to the OmniFocus inbox. Changes to actions on either side are applied to the corresponding items on the other side.