Nick Johnson's ENSv2 activation proposal bundles 15 smart contract calls from the DAO timelock into a single atomic transaction to halt new .eth registrations on the original v1 registrar

From the articleEthereum Name Service Team Asks DAO to Switch On ENSv2 and Freeze New .eth Sign-Ups on v1 - UnchainedAlso in ENS seeks approval for major .eth domain upgrade