In a post on its official blog, Tumblr writes:
We’re really proud of the new documents. We think they’re easier to understand and better for you and our community. In particular, we’ve clarified some of the content ownership language in our Terms of Service, dropped a few legal restrictions, and revamped our Community Guidelines to better reflect what we’re seeing and how we’re enforcing our policies.
It’s worth noting that, while the Community Guidelines have gotten longer, the only new policy in the draft that we weren’t already enforcing is “Promotion and Glorification of Self-Harm”. The other additions are meant to clarify our existing policies.
Tumblr says the new terms will be officially launched in the coming weeks, but it's accepting feedback.
The new Terms of Service are here.
The new community guidelines are here.