I'd prefer a single payment over driblets weekly, but not necessarily only at the beginning - I donated to both Fledgling and Saltation, but I couldn't have right at the start, so was very grateful others had taken up the initial challenge.

Please not PDF. an e-book is great for me, as good or better than hard copy, but pdf and my e-reader don't play at all well togother. HTML, txt, mobipocket, but not pdf.