"Ice Cube later came on Maher’s show and stated that the word can be used only by African-Americans or it would just not be acceptable."
  a few years back, at a party  i had this exact same discussion with a black guy i had just met. he used the word while talking and i politely asked him not too as it really galls me.  he told me it was a "cultural" thing within the black community.  i told him it was a "cultural" thing within the white community too. didn't make it right.
   a staring eyeball to eyeball stand-off ensued for maybe 30 seconds, my husband,  sister in law and  some of the other people around - all black - started cracking up. the guy said "you don't stand down do ya?" "nope - you don't either , do ya?" "nope....................come on in and fix a plate, ... we just dug up the goat"  (in inglewood, CA.!!.. buried in the ground BBQ type thing. NO thanks.  hubby smiled and whispered to me "it's a cultural thing"