Part of the reason for our requesst that you participate in our testing period is to gather feedback on ways to increase the value of Census API service to you.
I saw in another thread a mention of using SAIPE rather than ACS for Jan's app. It would be helpful to know which datasets are your highest priorities.
Please respond here to suggest which datasets would be most valuable to you as we extend API access to more of our statistics. We may have to make things available in a different order for reasons technical, regulatory, or other, but knowing your priorities will help us direct our energies.