If you're going to start doing Tumblr and are concerned about NWS, google for a program called Tumblr Savior and set that up.

Being on Tumblr or even using Tumblr Savior is a 'caveat user' thing, though. Reblogging is very easy, might be NSFW, and not Savior depends on people tagging things, and not everyone bothers to do that, especially with reblogged stuff. But it's at least better than nothing.