As PBS gets heat for programming it had nothing to do with, like 9/11
Truth movement documentaries on Denver stations or a syndicated series
co-produced by the George W. Bush Institute, the producer of the Bush
program calls on PBS to make their IDs more "this was a PBS program"
and less "we are PBS," or bringing back the production company logos
at the top of shows, with a distributor logo (the nod from UK's ITV
that ended in the early 90s in an attempt to reduce "clutter"--WTTW in
Chicago refused to air those logos, except, of course, for its own):

http://www.current.org/ptv/ptv1002walworth.shtml

It seems to me that PBS already has its logo embedded in program
logos, the little animation that runs every 15 minutes during their
tentpoles, the web site plugs (and the requirement that there be no
"masterpiece.com" or "antiquesroadshow.org," but pbs.org) and the
video offers with the "1-800-PLAY-PBS" number.  About the only other
thing they could do is a logo bug in the corner--but the stations want
that real estate for themselves.