Latest news today is that the Trump Administration is planning changes to the VWP that would require all applicants to disclose social media history for the last 5 years, phone numbers from the last five years, email addresses from the past decade, personal details of family members and biometric information.
Keep in mind that the USA does not have sterile international transit - so this would affect not only tourists to the USA but also anyone transiting the USA to get to Canada, Mexico, Central America, the Caribbean etc.