The ad, created by agency Whirled, has generated 476,022 Facebook status updates, 54,529 tweets and 1,875 blog posts since it was published.
Another ad from Google, promoting Google+ hangouts and featuring The Muppets, was a success across social networks with 2,659 shares in the last seven days, ranking fifth in the chart.
Echoing its viral successes at the end of 2011, Coca Cola entered the top five with just under 10,000 shares this week with its Spanish "superhéroes" adv.
The chart, produced in conjunction with Unruly, ranks ads according to the number of times they have been shared on Facebook, Twitter and the blogosphere.
Ads launched more than 30 days ago are not included.
1. Google 'Zeitgeist 2011' by Whirled
123,462 shares this week
All time: 534,950 shares
All time: 13,630 shares
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Consumers are so well-informed by their online research they no longer feel a need to visit car showrooms, which is a problem for Audi.
Digital marketing executives oversee the online marketing strategy for their organisation. They plan and execute digital (including email) marketing campaigns and design, maintain and supply content for the organisation's website(s).