Reality check, rap ain't music. It is low intelligence words to the background sound of something I could reproduce with a keyboard that costs roughly the same price as a couple of cartons of beer.
Like you said, it's a preference, and your preferenece isn't rap so you won't think it is good, even the good stuff.
Rap has just as much talent as other music. You know what it takes to play many rock songs? How many 70s and 80s bands played while high or drunk! It doesn't take much skill to belt out power chords. Heck, I've had my bass for less than a year and I can play along with most classic rock, grunge, or punk.
However, there is a difference between rap and hip hop.
As for low intelligence words, gansta rap give rap as a whole that stereotype. There are rather intelligent rhymes in hip hop and rap. However, I don't think hip hop or rap will be as good as it was in the 80s. Run DMC was very good. Beastie Boys are very good.
Most good hip hop tells a story, there's rarely repeating lines except for an occational chorus.
I like pretty much any music, though "classic" rock is my favorite. But look at most classic rock, it's the same verses and chorus repeated over and over.
Examples, "Cotton Fields" by CCR, or half of ZZ Top's or Led Zepplin's or Pink Floyd's songs.
I also have all of the White Stripes, Vines, The Darkeness, Yeah Yeah Yeahs, modern rock/alternative rock. Foo Fighters, Red Hot Chilli Peppers, more good modern rock bands. I also have modern metal like System of the Down, Korn, etc... Hmmm, headbangers ball...
I also like Gorillaz, what a cool concept. If you are going to fabricate a band, why not fabricate the entire band

Plus their stuff is good.
Heh, you should see my playlists. I always select random play on all my music. So you will get interesting style changes. Like motown to rap to classical to blues to punk to jazz to hip hop.
I just had White Stripes switch to Goo Goo Dolls to CCR to AC/DC to Magic Slim and the Teardrops(blues) to John Mellencamp to Eric Clapton to Blue Man Group to Green Day to Gorillaz to Korn to System of the Down to Linkin Park to Lenny Kravitz to Blues Brothers Soundtrack to Lynard Skynard to Andrew W.K. to Queen to Beetles to Doobie Brothers to Everclear to Jimi Hendrix to The Who to Warren Zevon to Tenacious D to Weezer to P.O.D to Rage Against the Machine to Santana to Moby to Shaggy.
I did use to like country, I can tolerate it now. Country just go so repetative, nothing really new. I know many will respond, "You liked country, you call that music." I will ask, have you ever played country? It runs along the same musical rules as blues, rock, etc... musically there isn't much difference, other than there's fiddles, banjos, and steel guitars

Of course, I will listen to Johnny Cash these days, yet.
Heh, I really need an ipod so I can have everything instead of what I can fit on a CD
But yes, there's alot of fabricated pop songs. What makes the top 20 of the country, the stuff MTV stuffs down teenager's throats and says is popular. And that's party due to the fact that kids have more time to listen and vote for songs or requests. How many of you adults request songs on the radio or just listen to what played?
But then, look at how much fabricated music was in the 80s. Synths could do most of the work.
I know people who hate the Beatles that "grew up" during that time because they think the Beatles are fabricated pop for the time. Of course, you listen to the studio recording that have been released they did alot of blues rock stuff that didn't make it to albumns. Cool stuff.