Read about a security breach that occurred over the weekend.
Via FastCompany:
“It’s not the first time Tumblr has had back-end troubles. The four-year-old site hosting 15 million blogs had a fairly basic security hole back in its infancy, three years ago, when users found they could access Tumblr’s system administration page just by adding “/admin” to a URL. Tumblr’s security has obviously become more sophisticated since then. But on top of the recent security breach, it has had problems accommodating its rapid growth, undergoing a site outage in December.”