Twitter Ramps Up Its Ad Plan Again, With Ads You Haven’t Asked To See

Coming to some of you, in about a month: Ads in your Tweetstream, from Twitter accounts you don’t follow.

In an incremental but important step for Twitter’s ad business, Dick Costolo’s company is going to start letting marketers place ads in front of people who haven’t asked to see them. Users won’t have the ability to opt out of the ads, either.

This is technically an extension of the ad product Twitter started selling a month ago. That one helped marketers place ads in front of users who were already following their brands’ Twitter accounts. The new twist to the plan will let advertisers place ads in front of Twitter users who are similar to ones following their Twitter accounts.

In discussions with ad buyers, Twitter is describing the concept, which will roll out to a small subset of users by the end of September, as “Promoted Tweets to users like your followers.”

That means that users who aren’t following Virgin America on the service might still see an ad for the airline in their “timeline” — if Twitter thinks they have things in common with people who do follow Virgin.

This marks the first time that Twitter will show ads to users who didn’t take some direct action to trigger them, either by following a specific account or by searching for a term on the service.

The company has always said it would get around to targeting users this way, but it has moved very slowly since it introduced its first ad products in April 2010. The company has ambitions of building up a big ad business — a la Facebook, if not Google — but it’s been incredibly cautious about the way it rolls out new ideas.

Twitter won’t comment specifically about the new ad plan, but offered up this statement via spokesman Matt Graves: “We’re always talking to marketers about ways they can get more value out of Twitter. While we have nothing to share about the way that the business might develop this fall, I can say the last month of testing for Promoted Tweets in the timeline has gone extremely well.”

Messages that Time Warner’s HBO sent out to fans of its “True Blood” show, for instance, were retweeted “nearly 1,000 times,” Graves said.

Twitter won’t tell buyers how they’ll determine which users are like other users. But the service already does something like that now, when it offers up Twitter users that are “similar” to ones you’re already following.

Like the “Promoted Tweets to Followers” that Twitter started selling this summer, the new ads will only appear on Twitter.com. And Twitter still can’t guarantee that Twitter users will see a marketer’s message — like its other ads, it will sell them using a modified auction, and only some buyers will get a chance to deliver their ads.

The big picture here is that Twitter is steadily trying to increase the number of places where advertisers can get their message across, without spooking users who generally think of Twitter as an ad-free zone. Twitter may generate more than $100 million in ads this year, but that’s not nearly enough to support an $8.4 billion valuation. Get ready for more.