Nicki has talent IMO but I don't think the people controlling her have let her be herself. Even though I haven't seen other female rappers do exactly what she does, she is basically a combination of lil kim (image) and Missy Elliott (offbeat flow, making funny sound effects in her raps etc) with a bit of her original style thrown in to fill in the gaps.
In her 'Black Friday' diss, lil kim actually said that Nicki was 'a put together gimmick, somethin like a collage' and I think she's right.
Hopefully Nicki will find her own style one day and have the confidence to go against the people who are making her copy others rappers so much.