First "Adult" Hip-Hop Album?

I was reading a review in Time Magazine of Jay-Z's Kingdom Come. And it essentially said that it might be the first "adult" hip-hop album. And the might was not whether there had been one before, but whether it in fact was adult. And I found this profoundly insulting. Apparently the reviewer doesn't listen to much in the way of hip-hop, because I can't imagine someone listening to Mos Def, Talib Kweli, Common, Tribe Called Quest, Lupe Fiasco or a variety of other artists and concluding that they produce albums that aren't adult. I won't go too far in what I think is underlying the argument that hip-hop is inherently immature, but I think it's bullshit. And Jay-Z's new album isn't that mature anyway.