NEW YORK: Tumblr and Twitter, the social networking sites, are planning new ad developments as they attempt to monetise their respective services.

Tumblr, recently acquired by Yahoo! for $1.1bn, will introduce sponsored web posts next month, reported Advertising Age. These will be integrated into users' streams in a similar manner to that employed by Facebook.

The move comes hard on the heels of Tumblr's introduction of mobile in-stream ads, with users of the site's apps seeing up to four ads a day.

Twitter is also reported to be taking a leaf out of the Facebook ad playbook with the creation of an ad-retargeting exchange similar to FBX. This would enable brands to retarget people who visit their sites with ads on Twitter.

"More advertisers today are ready to make bigger bets with retargeting and exchange-based buying because they're up to speed with Facebook or Google or Yahoo or AOL," Clark Fredricksen, vice president communications at insights provider eMarketer, told Advertising Age.

"The fact that some of the major advertising publishers have been doing that for a little while means that new players to the market can court advertisers with some experience doing this," he added.

Twitter also recently launched a TV ad targeting service to take advantage of the trend to dual-screening. A brand can monitor when an ad has aired on TV and then send out a promoted tweet to co-ordinate with it.

Separately, Twitter research found that promoted tweets that asked for replies increased responses by an average 334%, while promoted tweets with an ask to retweet increased retweets by an average 311%.

But this is leading to brands tweeting "the most nonsensical, cheesy messages" suggested Digiday, which quoted an anonymous brand executive who said simply that "it's the price to play today".

Matt Wurst, director of digital communities at 360i warned that brands practising this behaviour too often would "appeal to the lowest quality of user".

"Brands may ultimately grow their pages with the wrong people," he said.

Data sourced from Advertising Age, Techcrunch, Twitter, Digiday; additional content by Warc staff