They black out all items that get a DMCA complaint or similar request (so it's still there just not accessible). However they permanently delete illegal stuff.
I would assume they delete illegal stuff as they are compelled to. What I'd like to know is their policy for legal stuff that they exclude that is not as a result of DMCA.
If you ask them they will remove sites that you created. It's not under right to forget laws as they don't exist in the US. What I'd like to know is whether they also delete the data or just make it inaccessible.