Me and my girlfriend
It's long been considered a smart career move in Hollywood to hook up with someone whose career is doing a bit better than your own: find a fruit like Tom Cruise, marry him, pretend to have his baby, and the next thing you know, you're in the new Batman movie! I wonder if something similar isn't beginning to happen in the world of hip-hop.
Take for example Jay-Z. Not to suggest that his relationship with Beyonce isn't 100% genuine, but it does seem rather convenient to have a girlfriend with a career, since he hasn't had an album out in like three years now. He can drop a half-assed verse on her singles and have it played on the radio ad nauseum, and people will be like, Aww, how cute!
And if they go out anywhere together, it's an easy way to get his ugly mug in the paper. Given that he's currently over in Africa somewhere attempting to fix the water situation by rappin', I'd say the man has pretty much mastered the art of getting your name in the paper. Expect a wedding and/or well-publicized breakup conveniently timed to coincide with Jay's next album.
I've long suspected that Lil' Wayne mainly decided to date Trina as part of his post-the Carter policy of mimicking Jay-Z. The issues there are obviously myriad, but here's two: a) Trina is a disgusting beast of a woman, and b) Birdman, whom he considers his father, already ran up in that, which is just wrong. If anything, being seen with her might be damaging to his career.
That said, I wouldn't be surprised if Trina was the best he could do. I mean, I'm sure he could ride through any ghetto and find five bitches at random who are in better shape than Trina, but the trick only works if your girlfriend is somewhat of a celebrity . And let's face it: female rappers are a notoriously homely-looking, if not actually lesbian bunch.
Unless a rapper has gotten his life together - kicking it with Kofi Annan and Bill Gates - I imagine most R&B singers would be rather reticent to put themselves out there like that. They already saw what happened to Jennifer Lopez when she was with P Diddy. If you've already got a little money of your own, why even take the risk.
Meanwhile, if there's one group of women who could always appreciate a black man's dangerous nature, it's cracka-ass crackas. But rarely, if ever do you see a prominent rapper in well-publicized relationship with a cracka-ass cracka. As many jigs you see these days, especially bros with a little money, walking around with a white chick, this would seem less than likely.
Here's my theory: Rappers are afraid that they'll be seen as less real if they date a cracka-ass cracka. Black women, who are notoriously racist, will no longer buy their albums. Why go through all the trouble of recording your "song for the bitches" if none of them will buy your album? But I suspect that most prominent rappers are getting a lotta cracka-ass cracka tail on the low.
Or am I just making this all up?
 It should be noted though that Trina has taken the intiative to strike back at Gillie the Kid on Lil' Wayne's behalf, which is just rich.