Whenever someone jumps from one profession to another, it's always a cause for concern. And though people from all kinds of different careers are constantly trying to make the jump to the film world, I think the most apprehensive conversion is from rapper to actor. I'm not sure why, either, as most who have done it in the past have actually done better than, say, most wrestlers-turned-actors (hell, Sean "Puffy Daddy" Combs is the funniest part of Get Him to the Greek; and that's not a slight on the other comedians, he's just that great in it). There's just something about how bombastic and excessive the rap world is that doesn't exactly lend itself to the nuance of acting.
I haven't been swayed one way or another by Curtis "50 Cent" Jackson's acting career thus far. He's been fine in what I've seen him in, but what I've seen him in has mostly been smaller roles (save for his own biopic, Get Rich or Die Tryin') that don't really require too much depth. It seems Mr. Jackson would agree with that statement, since it's now become clear that the rapper-turned-actor has gone all out for his next role as a cancer-ridden football player in Things Fall Apart for director Mario Van Peebles.
According to ThisIs50.com, who provided the above picture as well as a second glimpse, Jackson lost 54 pounds over a course of nine weeks to physically fit the part. The diminished look is quite effective when you compare it to his normal weight, I think, but I also think we all know that weight loss or gain doesn't actually make you a better actor, it just makes you a committed one. However, in the case of Jackson, he may just pull off both.