There are some issues with the XFA beta that need to be resolved and for now I am going to ask that anybody hold off on donations to get access to the private XFA beta until those issues are resolved.
As soon as the beta is stable I'll make an updated post.
Dave, if you're still interested, please update your profile with the URL of your XF site. I am working on getting a new "XFA Testers" group configured and will need/like to know what sites are running the beta versions. Thanks.