While watching some Eminem's live performances I've noticed he performs Just Don't Give A Fuck with an angry voice, and the song itself then sounds angry. But, on SSLP, his voice had that nasal/high pitch that made the whole album sound like he's joking, so on a song like Just Don't Give A Fuck, every punchline comes out as funny and you don't take him seriously. You clearly hear it's him just joking.
In The Way I Am book he said he has no idea why he sounded like that on SSLP, so I wonder, if that voice wasn't intentional, was the whole SSLP meant to sound angry, like MMLP? If done with the tone MMLP has, or later performances of the song, they sound completely different, like they're written from a different perspective.
Perfect example
http://www.youtube.com/watch?v=gHMG3GH8hFA
It's like it's a different song.