Did they shut down and when did that happen?

No. Idea what happened didn't even know they were intending to shut it down, had many pervy friends on there. Oh well

Yes...so bummed out. I found out from another site that the newtumbl twitter account has the same message you see when you try to access the site:

It's been a blast.

Thanks for your patronage.

We hope you enjoyed your time at newTumbl.