X Factor 2014: 20 stars rumoured to take fourth judging spot

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X Factor 2014: 20 stars rumoured to take fourth judging spot

Melanie Brown (Mel B) has also guest judged on The X Factor before, and her outspoken manner would be a complement to Simon Cowell's, but the ex Spice Girl has recently signed on to judge America's Got Talent and schedules may overlap. Photo: © Getty Images