The name of the episode is a play on the boy band New Kids On The Block, who had been popular a few years before this episode.
The scene where Moe is about to cut Jimbo when he and Laura are making out is a reference to the rule in horror movies that when the couple makes out they get attacked or killed by the monster or the killer.
In the flashback when Jimbo puts Bart's head in the toilet, Bart's shirt is light green (rather than the usual orange). So it is likely that these are younger versions of Bart and Jimbo.
One of the WB's ads for the show, titled "Homie: the Buffet Slayer" (a parody of the series Buffy the Vampire Slayer, complete with its theme music being used for the purposes of the ad.) featured scenes from this episode (specifically the scenes where Homer took the "all you can eat buffet" slogan for the Frying Dutchman literally).
The "Northern Exposure" theme plays as Homer chases away a moose from the Simpsons' trash.