The random link button was probably removed for censorship reasons. Junior makes one click trying to find some cool random thing, and *BANG* porn site, warez site, l33t HaCK3RZ site. There may also be some technical details involved, like the CPU time consumed picking a random site out of an extremely large database.

Granted, Junior could also have clicked on Entertainment > Movies > Genres > Adult or thrown the word porn in the search field. The only difference is, those would be intentional, the random button would not.