enough ... Twitter does not use the 'nofollow' tag or disclose the fact that these are ads at all, except by defining them under the CSS class 'promo,' which is visible only if you look at the HTML
code," Mashable notes. As has been widely reported, Twitter has been experimenting with various ad formats and potential revenue streams over the past year, while concerns mount that the social media
star is losing its way.
One initiative, debuted in November, involved adding ads to individual user streams, while another let select customers advertise through Promoted Tweets, Trends or Products. Adds Mashable: "The text ads on the homepage probably aren't as important for Twitter as other ad formats, but the company is methodically trying every possible advertising avenue to figure out what works best."