Starting on May 2, advertisers will be able to buy the privilege of slapping their logo on the Tumblr dashboard. David Karp, the company's 25-year old founder and CEO, detailed the new revenue-generating effort at the  Ad Age Digital East conference. But as Karp took great pain to communicate in an interview with Ad Age's David Teicher a few days ago, Karp took pains to say that Tumblr isn't getting ads per se. They're getting "user-oriented promotion features." We don't mean to sound like a thesaurus or anything but some other words for this type of unit is "advertisement," "commercial," "promo," and "sponsorship."

This marks the end of an era for the infectiously popular blogging platform, popular with teenage fashionistas and hipsters alike. According to Kunur Patel, who was at the conference, Karp called "himself an 'idiot' for saying advertising turns his stomach in 2010." Turns out brands really want to get to know some of the demographics that spend hours a day blogging and reflagging and liking content on Tumblr. Why? Because there are a TON of them. 50 million people blog on Tumblr, Karp also said at the conference's keynote, and 122,000 new users joined the network on Tuesday alone. For a site that's less than five years old, Tumblr is comparable to Instagram in popularity, and it's still independent. Now, it sold itself out to advertisers—or, "user-oriented promotion creators"—just like the rest of those free Internet websites that everybody loves so much.