'About the only thing that could be said of them is that they reflect a certain reality about society ... but it is that reality within society that we all consider to be pathological and regrettable, a condition of physical, moral and spiritual degradation.'
Now, I know you know better than this 'we all' business...
Eminem is offensive and piggish... that's his image. However, the two songs you chose to quote are quite possibly the worst you could have quoted and are hardly representative of his lyrical talent, which I believe he has quite a bit of. It's as bad as proof-texting the bible for passages supporting your point as ignoring those that don't. For example, look at this set of lines from The Way I Am:
I sit back with this pack of Zig Zags and this bag
of this weed it gives me the (s) needed to be
the most meanest MC on this -- on this Earth
And since birth I've been cursed with this curse to just curse
And just blurt this berserk and bizarre (s) that works
And it sells and it helps in itself to relieve
all this tension dispensin these sentences
Gettin this stress that's been eatin me recently off of this chest
I really honestly think he uses rhyme in a very effective way, especially coupled with the way he reads the lyrics in the song. Now, regarding Lose Yourself (which I also consider to be a very poetically sound song):
His palms are sweaty, knees weak, arms are heavy
There's vomit on his sweater already, mom's spaghetti
He's nervous, but on the surface he looks calm and ready
to drops bombs, but he keeps on forgetting
what he wrote down, the whole crowd goes so loud
He opens his mouth but the words won't come out
He's chokin, how? Everybody's jokin now
The clock's run out, time's up, over - BLAOW!
Snap back to reality, OHH - there goes gravity
OHH - there goes Rabbit, he choked
He's so mad, but he won't
Give up that easy nope, he won't have it
He knows, his whole back's to these ropes
It don't matter, he's dope
He knows that, but he's broke
He's so sad that he knows
when he goes back to this mobile home, that's when it's
back to the lab again
I really, honestly think the imagery and rhyme style here evokes a tone that is appropraite to the subject matter and effective in moving the listener. Look at these lines from later in the song:
'All the pain inside amplified by the
fact that I can't get by with my nine to
five and I can't provide the right type of
life for my family, cause man, these God damn
food stamps don't buy diapers,'
This is honest look at trailer-park society. This is a look at the poeple to whom we, as a society, delegate the term 'white trash.' This is life for people without money, this is life that ain't no crystal stair, it's hard and it's mean but it's life. It's truth and it's spoken in (to me) a suprisingly poignant way from a rapper with a hard-ass edge... but a talent for evoking empathy from at least some of his audience.