According to one recent analysis, over 11% of Tumblr’s top 200,000 domains are full of “adult” content. Yes, a big part of Tumblr is the porn – it’s not the biggest part by any means, but it’s significant. And ever since news of the big Yahoo acquisition, Tumblr users have worried that Yahoo may attempt to clean up Tumblr’s image by controlling certain types of content.

Fear not, Tumblr users. Your porn isn’t going anywhere.

For the first time since the acquisition announcement, Yahoo CEO Marissa Mayer has made a clear decree on her company’s role in censoring content – mainly that they have none. During Yahoo’s new Flickr event Monday night in NYC, Mayer was asked directly whether she will restrict content on Tumblr.

“No, we won’t,” she said. “It’s the nature of user-generated content.”

She continued on to say that it’s important to have community tool like “NSFW” tags that Tumblr already has in place. There you go, folks, that’s about as definitive as you’re going to get.

Before those remarks, Mayer had been a little more vague about Tumblr’s porny bits.

“The width and breadth of content on Tumblr is what’s exciting and has allowed it to reach more users.” she said during a conference call Monday morning. She also said that Yahoo would have to make use of good ad targeting, to assuage any concerns from future advertisers. And there will be more ads inside Tumblr, that’s for sure.

“We promise not to screw it up. Tumblr is incredibly special and has a great thing going. We will operate Tumblr independently,” said Mayer during her announcement.