LeAnn Rimes flip-flopped big time on her bizarre performance last night on "X Factor" -- backing off her rep's statement to TMZ that she seemed off because she was "helping" her 13-year-old duet partner -- so SOMEONE'S lying ... and we might know who ... Plus, Mike shows how Jessica Simpson's dramatic weight loss could be an optical illusion -- using his own body ... And the return of ... TIM'S REJECTS!!!