Funding a Kickstarter project creates a legal obligation on behalf of the project creator to provide the reward for the donated amount [0], even if the project itself is ultimately unsuccessful.
Of course, should a project go so off-track that a backer is compelled to seek a refund their claim is against the creator, as Kickstarter disclaims any responsibility.
I was addressing calinet6's comment that one should expect nothing from a Kickstarter project. Sorry if my comment came across as implying you weren't fulfilling the rewards; it was meant in the generic sense. It's awesome that you're on top of things.
Of course, should a project go so off-track that a backer is compelled to seek a refund their claim is against the creator, as Kickstarter disclaims any responsibility.
[0] http://www.kickstarter.com/help/faq/kickstarter%20basics#IsA...