R'n'b's current electronic angle is also interesting

Indeed! But I'd say that this derives from the Dirty South and Miami bass and dancehall. Of course, Southern hip-hop has always had way more interplay with club music than Northern hip-hop has, so the South's current commercial dominance just means that more people are aware of the electronics, not that it's new. But its use in a big way in r&b may be relatively new. Or maybe not. I'll have to think.