Okay, so apparently, this song is many people's least favorite. Me? I think it's catchy as fuck, and the voice is annoying, but somewhat funny. Want to know the backstory? Sure, you do, since you hate the song so much.
So it goes back to The Eminem Show, in 2002, where it just came out. Apparently, Em was reading one of the reviews, that said he was going soft (which was completely wrong) because he wasn't going as hardcore as in his last two albums. This pissed him off so much, he wanted to make a diss track aimed at the reviewer. The song was an unfinished minute long song called "Superman is Fucking Gay", with an annoying as fuck voice, an exaggerated self-parody of his high-pitched SSLP voice mixed with his Cartman impersonation, and some of his nastiest lyrics.
In July 2002, he finished it during the 8 Mile-era, intending to release it as an extra feature on the soundtrack. This never came to fruition, and he merely forgot about it. Though, in December, he replaced one verse, which was paying homage to the similar South Park episode. A reference to Jenna was added to one verse, also. Later, the early 2002 unfinished version leaked along with the Encore leak, which outshined it, and the song slowly disappeared from all leaks. During his drugged-out period, he wanted going to put it on Encore, but again, it never came to fruition. Finally, as a joke, he put it on an album intended to have his biggest hits.
Oh yeah, and at the end, he's telling the harsh reviewer to stick a gerbil up his ass. So, basically, this was started in February 2002, and finished in December 2002, as a diss track aimed at a young reviewer who bitched about wanting more hardcore Slim Shady shit. And all this shit got buried under all the hatred.
You just learned something today, and I just taught you about something.