With $4.71 billion in “digital” revenues, WPP Group is the biggest digital player on Madison Avenue by a substantial margin, according to estimates from paidContent’s top 50 global companies based on digital media revenues. Dentsu, which is poised to acquire Aegis Group, ranked No. 2 among ad agency organizations with an estimated $2.90 billion in digital revenues, followed by Omnicom ($2.78 billion), and Publicis ($2.19 billion), Hakuhodo ($719.2 million). None of the other major agency holding companies -- including Interpublic, Aegis, Havas, MDC Partners, and Cheil -- ranked in the 2012 edition of the paidContent 50, which was dominated by companies other than advertising agencies. Not surprisingly, Google ranked a dominant No. 1 with $36.4 billion, followed in a distant second place by China Mobile’s $7.58 billion. Top-ranking agency group WPP ranked only 7th, behind Bloomberg ($7.00 billion), Reed Elsevier ($5.93 billion), Apple ($5.40 billion) and Yahoo ($4.99 billion).