[rotnewson]

Since no one explained it, it is whois spam. You can find more info through searching, they are not hacked they are just popular sites so they attract the spam.

And if you don't want to google people just register name servers with xxx.com.xxxx.tld and their name server will show up when someone searches for xxx.com

[enegdo]

Does this have any relevance other than someone claiming they "hacked" a certain domain? I don't imagine it has relevance on SEO or anything else, right?