Privacy took a big step forward with this move which means you can now get TLS encryption for .onion domains operating within the Tor network.
The Internet Assigned Numbers Authority (IANA)—a department within the organization that oversees the domains of the internet known as the Internet Corporation for Assigned Names and Numbers (ICANN)—along with the Internet Engineering Task Force (IETF), designated the .onion domain, used for sites hosted on the Tor network, as a “Special Use Domain,” giving it an official status that it previously lacked. IANA and IETF Designates .onion Domains Special Use [motherboard.vice.com]