The popularity of a movie like "Barbershop" is proof of this. More and more blacks are getting sick of ebonics, gangsta rap, and white left wingers defending the right of young blacks to address each other as "nigga'".
I don't know where you are getting your facts from, but a Hollywood movie is not a reliable source. Even if I were to buy your unsubstantiated assertion (I don't) that "blacks are getting sick of gangsta rap," the popular culture has embraced rap music and the dress. It is mainstream and selling bigtime.
Blacks have always set pop culture trends going back to the 1920's. Every white kid, Asian kid, Hispanic, European, etc, will copy the way blacks dress, speak, their music, etc.
The difference between the era of jazz, blues and even classic soul music and the current era of rap is that blacks used to take pride in their neighborhoods and aspired for something better. These days, young blacks have advantages and opportunities that their parents and grandparents didn't have, and instead of taking advantage of it, they walk around in $200 sneakers, take pride in being illiterate, and worship mafia culture.
Many blacks are rightfully concerned about the future of the black community. So regardless of how many white kids from the suburbs copy black style, there is a huge crisis in black America. Bill Cosby, black ministers, black conservative writers, etc, are speaking out and many are starting to listen.
Meanwhile, there is also an emerging class of black yuppies who are getting out of the ghettos, getting good jobs and grooming their children for a better life. They may be criticized for "acting white", but in the end, they will become the example that other blacks will try to follow. Condi Rice is a perfect example of someone who, on one hand, is a role model to ambitious blacks, and on the other hand, is intimidating to the ghetto culture that glorifies eternal victimhood. I'd love to see her run, just to see what the reaction would be from blacks as a whole.
And I still say the popularity of a movie like "Barbershop" is a significant sign of progress.