It seems like Tumblr's filters at least functioned well enough to avoid any significant damage to the server or websites themselves. I suspect Tumblr will linger on longer than Livejournal did simply because there isn't any major fandom-based alternative available right now, but I imagine this is the start of a series of increasing dumber moves on their part.

The one outrage they spared their users from was enforcing the rules AFTER convincing people to do premium and paid accounts. That's really where I think LJ really was obnoxious. You don't have people pay you for your website services and then do a bait-and-switch on the TOS because it serves somebody else's purposes.