"I Care 4 U," in three words: Usher's dubstep song.
OK, that's reductive. Sure, there was no way Looking 4 Myself was getting off anyone's hard drive without a dubstep track, or at least a dubstep breakdown, attached, and this is that track, smudged throughout with big, obvious bass wobbles and Slinky-supple synth work. You'd never mistake this for, say, something by Benga or Skrillex (it's a Danja production), but you'd also never mistake it for anything else.
But focusing on that is the least interesting way to hear "Looking 4 Myself." A clue's in the title, the same as one of Aaliyah's singles. Usher's "I Care 4 U" isn't a cover, but almost everything about it is nevertheless a throwback--namely, to Danja and mentor Timbaland's '90s and early-'00s R&B work. You'll hear this everywhere; the way Usher glides over his melody, just off the beat, his spoken vocals, or the massed strings and falsetto backing vocals later on. It's hard to go wrong with '90s revivalism now, but even if it weren't, the two styles temper each other. The modern elements keep this from sounding like pointless retrofetishism, and the classic foundation keeps the dubstuff from seeming too blatant. When Usher bragged about blending genres, this is probably exactly what he meant.