Twitter as Tech Bubble Barometer - WSJ.com
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| Getty Images - Twitter co-founder Biz Stone, left, during an announcement of the newly revamped Twitter website in September. |
One of the new twitter ad services, called Promoted Trends, has been selling out its inventory every day, said one person familiar with the matter. The other two ad products, Promoted Tweets and Promoted Accounts, are also doing brisk business, this person said.