Once again, unaccountably it was a big week for the nightly news shows with NBC averaging 9.5 million viewers for NBC Nightly News With Brian Williams. (The Associated Press observed that the figure would have put the newscast among the top 20 shows in primetime.) ABC World News With Charles Gibson placed second with 8.1 million viewers. And even CBS Evening News with Katie Couric performed respectably, attracting 7.3 million viewers.