Twitter Promotes Costolo to CEO, Launches Promoted Accounts

Twitter CEO Evan Williams handed over command of Twitter to COO Dick Costolo, who was largely responsible for getting the startup's ad initiatives running, including the new Promoted Accounts.

Twitter crossed another threshold in its evolution as a major advertising platform Oct. 4 with the ceding of the CEO reins by Evan Williams to COO Dick Costolo and the launch of Promoted Accounts.

Williams, who created Twitter along with Biz Stone and Jack Dorsey after selling his company Blogger to Google and leaving the search engine, said in a blog post he will focus on product strategy going forward.

Williams explained that after the successful redesign of Twitter, he realized that he is "most satisfied with pushing product direction. Building things is my passion, and I've never been more excited or optimistic about what we have to build."

The timing of the move to put Costolo in charge is telling. Twitter has grown to more than 300 employees serving 165 million Twitter users who blast out 90 million tweets each day. With such scale, Twitter needs to focus on making money to help its investors recoup their $100 million-plus of funding in the startup.

Under the direction of Costolo, Twitter launched its Promoted Tweets and Trends ad products, allowing advertisers such as Starbucks and Virgin to pay to have their tweets listed as the top result when a user searches

Businesses with products and services to push pay $100,000 for these links. Williams acknowledged Costolo's efforts for the Promoted Tweet suite, calling him "a critical leader in devising and executing our revenue efforts."

Costolo, who like Williams joined Google after selling his company-Feedburner-to the search engine, has been a fixture on the keynote circuit since unveiling Promoted Tweets.

The new CEO said at Interactive Advertising Bureau's Mixx conference Sept. 28 that Twitter will soon suggest accounts that people don't follow but may find of interest.

This product, dubbed Promoted Accounts, launched an hour before Costolo was officially given command of the company and builds on Promoted Tweets and Trends. The goal of Promoted Accounts, according to a blog post, is to introduce more accounts to people.

Promoted Accounts are suggested based on a user's public list of whom they follow. When an advertiser pays to promote an account, Twitter's algorithm looks at that account's followers and determines other accounts that those users tend to follow.

If a user follows some of those accounts, but not the advertiser's account, then Twitter may recommend the advertiser's Promoted Account to that user.

Beginning this week, users who are logged in may see Promoted Accounts surface in the "Suggestions for You" section in the side panel on the right side of the homepage.

Twitter also said it is opening Promoted Tweets and Promoted Trends to third-party partners, starting with HootSuite today and others in the future.

HootSuite will run Promoted Tweets in search and highlight Promoted Trends, taking an unspecified cut of Twitter's revenue for these products.