I was expecting the article to reveal a new service that is competing against Facebook, Twitter and Tumblr. I suppose that says something about Tumblr -- at least in my eyes it's pretty well established.

Yes, or: "Meet Facebook and Twitter’s New Rival: Tumblr".

But, maybe the headline-writer was intentionally vague. People who already know about Tumblr, Facebook, and Twitter might be more likely to click if they thought the article was about a new fourth company, competing with all of them.

In the old world, where you'd already bought a magazine or newspaper, the incentives of headline-writers and readers were more aligned. Sure, the headline should be interesting --- but also accurate in a way that saved the customer's time. Only the front-covers as shown on newsstands -- before the purchase decision -- needed spin to steal attention.

Now, every single click is a sort of 'purchase decision', and every headline subject to the perverse incentives of the newsstand, where the reader's time is something to be stolen. Sometimes confusing people gets more traffic than informing them -- so we get intentionally misleading or inflammatory headlines.

Anyone want to collaborate on a web service that re-headlines links to curb attention-grabbing abuse?

Or an apostrophe after "Facebook," I think.