The trend of bringing celebrities has also caught up with X Factor (US) and Mariah Carey may be the first on board to mentor Simon Cowell's contestants for the show.
Carey reportedly is in last stage of negotiation with Simon Cowell.
Simon would judge X Factor along with Paula Abdul, L.A. Reid and Nicole Scherzinger. All the four judges would pick up a celebrity mentor to train their contestants.
Sources reveal that Usher has been signed for X Factor (UK). Talks is also on for roping in singers like, Beyonce and Rihanna for the US show.
The reality show would premier on Fox this September