so here's crack's take on Fif:
he changed/revolutionized the rap-game by making album-format mixtapes a 'thing'. most current rappers in the game right now owe him that, straight up. his first album is a classic and he has had some of the biggest hits in the 2000's ("In Da Club" is one of the biggest rap records ever, no denying that.)
that's all in the past though. the main flaw with 50 cent in 2012 is that he never fully developed/grew as an artist. 50's main draw was how hard he was, his cockiness, his whole tough-guy attitude/image, but we never really got too much depth from him as a writer. lil hints of it here and there, but it seems like 50 just wanted to give us this hard, gangster persona that beefs with everyone. all that negativity got old and people were over his bullshit. he bodied people left and right, but lost his edge when dealing with Game and Rick Ross when it comes down to it.
the man is really talented and funny as fuck imo, but he just doesn't have that "it" factor anymore. he's stuck in 2006 musically and needs to progress as a musician/person.
(a good example of his lack of creativity is all the shitty tracks he's hopped on the last year or two. "Like A G6" remix, that song with E-40/Too $hort, his songs with Jeremih and Soulja boy. he seems like he's desperate for radioplay/hits, so he's hoppin on other people's hot tracks atm, which is something he'd never do before.)