Hey Chad, I wonder if Apple would allow a Gittip app using in-app purchases? They just released subscriptions too. That way every downloading user would already have his CC on file, and be a click away to donate.
https://github.com/whit537/www.gittip.com/issues/111
Who are the players here?
https://github.com/whit537/www.gittip.com/issues/65
The basic Gittip roadmap is to get the full circle working once with the most common case (credit card in, ACH out), and then iterate from there.