[Andrew]

We don't at this time have any plans for a Blackberry app.

Some people sync OmniFocus with iCal, and then use The Missing Sync (third-party software from mark/space) to sync iCal to their Blackberries. There are some limitations with this approach (it's certainly far from equivalent to what you get with OmniFocus for iPhone, for instance), so I recommend carefully exploring it before committing to it, to be sure whether or not it is sufficient for your needs.