As interactive advertising gains market share, broadcast advertising is
responding by becoming ‘rationalized’ and possibly commoditized. The
process of buying broadcast advertising is becoming more efficient, with more
resources available to measure its effectiveness. One of the big drivers of this
evolution is Google, but they are not alone. They just bought a company that
brings radio advertising within reach of small businesses, called dMarc Broacasting (see excerpt below). Another
company, Spotrunner, allows companies to
select a tv commerical template, customize it and order local market tv time
effectively. Templates allow inexperienced marketers to leverage more
sophisticated ad formats.

To measure broadcast (and with Google, even print) advertising, these
companies are all pushing advertisers to use 800 phone numbers and specific
internet landing pages in their ads which allow the media company to compare the
ads’ performance. Another great side benefit of this system is that small
companies receive an external database of inquiries, helping them track their
prospects. Since small companies are often very sloppy in keeping track of
leads, we expect sales productivity to improve as well.

WSJ.com:
Google Steps Further Into World of Old Media by Kevin J.
Delaney (subscription required) 

The radio deal is the latest of a series of recent moves by Google
  in which it aims to bring its Internet advertising expertise to bear on
  old-media markets. Since last year, Google says it has been placing ads on
  behalf of advertisers in three magazines and the Chicago Sun-Times newspaper.
  And Chief Executive Eric Schmidt late last year acknowledged in an interview
  that the company is considering extending its ad system to TV advertising as
  well.