This is useless
Owners of malicious websites can simply detect that someone visiting their site is a McAfee bot or a normal visitor. They can serve clean content to the McAfee bot and malware to the normal visitor.
This is just another attempt by the ICM Registry to make their new tld look better than it in reality is. Heh, the adult industry doesn't even want the .xxx tld so ICM is desperately looking to add what may look like value to some but is in reality useless.