Yes can FFMS serve out the PDF files when working with iTunes U content. When working with PDF files in iTunes locally, iTunes send the PDF to either Acrobat or Preview. I see firefly really helping out schools as drive storage is cheap but bandwidth and local DVD libraries are not as well as archiving old VHS stuff and making it available school wide when more than one teacher needs it, or just for convenience. All of our projector carts have computers but not VCRs or DVD players (well the comps can play DVDs). This would also be way cool if we could afford enough AppleTV or similar boxes to play back all this stored content on the TVs in each room.
Yes I am an optimist and dreamer. 🙂