Be careful, on the 4th of July, many users who are feminists decided to post feminist things on 4chan and upset many users. Now the people of 4chan are retaliating even worse than what tumblr did.
On various tags, 4chan users who created tumblr accounts are posting gore, rape based images and many more disturbing images on various popular tags. Please be very careful as your surfing tumblr.
Also, be sure to make sure your tumblr account is secure because they are also planning to hack accounts to post this stuff too.
Regardless of what tumblr did, I feel like the retaliation of 4chan is sickening and so many people already have been triggered by their exploits. I'm deeply sorry for anyone who has seen this stuff already.. Be safe.
Here's a journal detailing what happened here.