It can't be any fun fielding press queries about layoffs, reorgs, and hostile takeover three times a day. Add to Yahoo PR woes: Bitchy coworkers. Last night, a tipster sent us an account of a few "chatty Cathys" from Yahoo PR who, after a few drinks, were only too pleased tell anyone who would listen that "heads on the PR team need to roll." Yes, they named names — including the hapless Brad Williams, the target of an accusation in August that he was sleeping on the job at the company's annual meeting, a charge Williams strenuously denied.