A few weeks ago, Tumblr founder David Karp rather abruptly announced that he was reversing his long-held anti-advertising stance and opening Tumblr Radar up for sponsorship. According to an email from Tumblr communications rep Katherine Barna, the ad shop is officially open for business.

"We're very excited to announce that Tumblr's first official Sponsor products are now available to advertisers!" Ms. Barna wrote, directing folks to a new page for potential marketers. "We are constantly delighted by the creative ways that brands use Tumblr, and are confident that the world's greatest marketers and media companies will use these products to set a new bar for creative advertising on the web." Mr. Karp seemed a little more contemptuous towards advertisers at the Decoded Fashion conference earlier this week. But, like, in a friendly way, of course!

Sponsorship packages, which will appear on the Tumblr Radar (that little box on the right of the dashboard) as well as on Tumblr Spotlight, start at $25,000. As suspected, The Hunger Games producers have already signed up with an ad for Capital Couture, a marketing site set in the fictional world of film. If Christopher Nolan is reading, we would a 100 percent click on absolutely any The Dark Knight Rises-inspired Tumblrs you want to promote. We'll even pretend to believe you when you call it "augmented reality."