A quick search of the web resulted in nil serious information about Halberstam's 'The Best and the Brightest' (1972), one of the most important - journalistic - contributions to power elite research (centering on the Kennedy years) in the tradition of C. Wright Mills. There might be just one article on the web (by Nünlist) discussing Halberstam intelligently...

...and just to be complete: Halberstam's other book on the American power structure, his comment on the rise of the media - 'The Powers That Be' (1978) -, is equally absent. Halberstam himself seems to have resigned (or just gotten wiser?), see this interview...