A blog post by the company's Yancey Strickler outlines the changes, which mostly deal with cleaning up the language, trimming the legalese and making it "straightforward and to-the-point". Strickler also mentions that a bit of work has gone into explaining "what's expected from everyone involved in a project":
For the overwhelming majority of projects, it's pretty simple: creators finish the work they planned, backers are happy, and nobody sweats the details. But there are exceptions. Sometimes problems come up, projects don't go according to plan, and people wind up in the dark about what's supposed to happen next. So we're spelling it out -- what's expected from backers, what's expected from creators, and what needs to happen if a project runs into trouble.
The specifics are provided in section four of the document. Essentially it states that a creator must finish their project and provide rewards once funding is complete. If, for whatever reason, these obligations can't be met, the creator must "make every reasonable effort to find another way of bringing the project to the best possible conclusion".
It then lists the actions the creator must take and revolves around providing a clear explanation as to what went wrong and how the money was spent. It's simple stuff, really, though the final point is interesting:
They offer to return any remaining funds to backers who have not received their reward (in proportion to the amounts pledged), or else explain how those funds will be used to complete the project in some alternate form.