Sharon Osbourne and Dannii Minogue sharpen their claws
But what a difference two-and-a-half years can make as Sharon, 58, has been hotly tipped to return to the show this year - leaving Dannii, 39, incandescent with rage.
‘Everything's still very much up in the air,' says a show insider.
'Names are being bandied about but the one that keeps cropping up is Sharon. She was very popular at the judges' houses stage with Louis Walsh last year and she's always had a huge following.
'The problem is that Dannii hasn't been consulted and she's fuming.'
The pair have been at loggerheads ever since they first appeared on The X Factor together in 2007 and Sharon later cited Dannii as the reason she quit.
To make matters worse, when the Australian judge released her autobiography Dannii Minogue: My Story last September she accused Sharon of bullying, which reignited their long-running feud.
‘After all she went through with Sharon, she just can't face her live on TV again,' says a friend of the Aussie singer.
‘She feels she hasn't the strength to fight with her. She can't believe the producers would do this.
'She's beginning to think she should have stuck to her original plans to quit as she isn't prepared to put herself through the mill over Sharon again. It's not worth it.'
Read the full story about Sharon Osbourne and Dannii Minogue in Now magazine dated 31 January 2011 - out now!