Absolutely. At the very least this guy will help you read between the lines and act as a good gut-check to your interview experience.

I would reiterate what Tom_B said about greater responsibility but I think it should be noted the kind of non-profit he worked at. Depending on organization, its mission, and people non-profits can be no better than the corporate machine.

Talking to the former director would lend some valuable insight into the culture and what its "really" like on the day-to-day.