Sources within CBS News are hinting that Katie Couric may leave the network before the end of her contract, possibly as soon as January, according to the Wall Street Journal. Ms. Couric was initially signed on until 2011, but has had trouble justifying a $15 million paycheck amid two years of record low ratings for “The CBS Evening News.” Despite issuing a statement Tuesday denying any personnel changes, CBS executives are currently investigating which prominent news personalities are nearing the end of their contracts, the paper reports.