Publicis' poor results and the market's reaction raise questions over the broader ad industry.
Organic growth was only up 0.4% in Asia-Pacific
Admission of error by social network comes just two months after previous mess-up.
Weed retired from Unilever in May.
Those who spent the most time working with media agencies had lowest opinion of them.
Nakamura's appointment is another sign of Tim Andree's 'one Dentsu' vision.
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