Simon Cowell and his sharp tongue are back! On 'The Tonight Show With Jay Leno,' Cowell offered unfailingly honest opinions of his fellow judges on 'The X Factor,' which is set to premiere tonight.

Interestingly, Cowell's most scathing (and funniest) comment had nothing to do with the famously loopy Paula Abdul. (Although he did compare Abdul to a "lost dog.")

Instead, Cowell called former Pussycat Doll Nicole Scherzinger "fantastically self-centered" and "nuts," pointing out that she unintentionally developed a different accent at each city they visited.

As for record exec L.A. Reid, Cowell wasn't any nicer. "I've kind of met my match with him... he's very, very difficult to work with. Very petty," he said.

[via Gawker]

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