And that’s where a collision with Tumblr is most likely to occur: just like BuzzFeed, the blogging network has grown at a phenomenal rate over the past year or so — briefly entering the top 10 list of U.S. websites with over 200 million visitors per month and 18 billion pageviews — and it also has a fairly deep war-chest of cash that it has built up through a series of financing rounds. But just like BuzzFeed, the blog platform also has to find a way of generating enough revenue to justify its valuation, and native advertising is the most likely method of doing so, especially when Tumblr seems ideally suited to visual advertising.