Great idea, can the page be branded under my startups name or is it app.net?
fwiw I have personally witnessed a significant percentage of consumers accusing a crowdfunding project of being a "scam" if it is hosted on their own domain rather than an impartial 3rd party like Kickstarter. I think that is one of the reasons consumers like Kickstarter vs self-hosted crowdfunding.
Additionally, in the Bitcoin use-case, if you have a page on your subdomain powered by Backer that accept Bitcoin, consumers will be confused and angrily say that you already accept Bitcoin because that page exists. That is also something we learned first-hand.
I think we'd go with credit card option as that's what we plan to use on the site
Either way it's awesome idea congrats on launching