Eminem aside, rap and hip hop certainly havn't been adopted by white music culture to the extent that the twelve bar blues became a mold for white rock'n'roll and eventually white rock or even to the extent that black soul music shaped blue-eyed soul.
Most 15 year old white boys are trying to be gangsta and don't even wanna hear anything with a prominently featured guitar in it with the notable exception of the new Daft Punk. There are exceptions obviously (there's still metalheads, punks,etc, but they're not in the mainstream). Hip Hop sensibilities are easily dominating pop music now (production and backing music style, many pop songs have rapped lyrics over the bridge or break at least, many of of those by a guest star MC etc - if it isn't an outright Hip Hop track). Blues is played out, as someone who very recently was in a very blues based band, the kids don't wanna hear it (hell, the young adults and those my own age don't want to hear it).
Today's top 40:
1 Miley Cyrus (current single is a ballad, but a) she 'twerks' and b) total hip hop style production usually)
2 Katey Perry ( total hip hop backing track, maybe less so the choruses - but whole note guitar is hardly blues)
3 Royals (never heard them before just now, but that's definately Hip Hop influence)
4 Awicci (OK you got one so far.... maybe - kinda folky)
5 Robin Thicke (total hip hop backing track and 2 guest rappers.... he's like a white Nate Dog but with nothing relevant to say and nicer clothes)
6 Drake (he's even black!
)
...
(and these are just the easy case ones on the rest of the first page of the list):
....Eminem is at 11, JayZ and Justin Timberlake at 14, another Robin Thicke w guest rapper at 18, Big Sean, Lil Wayne & Jhene Aiko at 22....
There isn't a solidly blues-based song in the bunch.
The only people left carrying the torch are Harde Blues Dades (bit of an in-joke from another board I am on but this guy pretty much summarises it):
