@ehBeth,
In the a2k world of data, the first post constitutes the thread. So if that is marked the thread is marked.
If posts are marked it just collapses the post and users can click to see it or set the preference to never collapse it, but it does not mark the thread.
There may be times, where a moderator may just mark the first post, and thusly the thread, due to an enormous number of individual nsfw posts to it, just to make things easier.
So to recap:
Topics that are "nsfw" only get a red nsfw next to the tags. That's it.
Posts (most of which that used to be censored by removing the images or graphic content) that are marked nsfw are collapsed, but can be opened at a click or members can opt out of the collapsing.
I think on the balance of things, it actually adds up to
less censorship and makes the ability to support such discussions entrenched as part of the community.
But hey,
some people just need to throw things on the ground.