From Publishers Lunch, regarding the Random House building:

All Clear At Bantam Dell

Though the 24th floor offices of Bantam Dell remained shuttered yesterday and many Random House employees were still working from home, at about 5:30 yesterday the company informed its people that after "waiting for results that we could share with everybody," the company was told "that the results of all preliminary lab reports (including tests for anthrax) are negative." The 24th floor has reopened today, and all employees are expected back at work.

Sorry for the false alarm yesterday.