Well, when I tried posting replies to some members on one of my threads, I saw that the reply posts were being bundled up into one single "flow" of replies.
Here:
https://www.pentaxforums.com/forums/12-post-your-photos/251200-nature-big-whi...-took-off.html
At that time, I wasn't aware of this new "system" and thought that the forum had gone weird, until someone was nice enough to point this new thing to me.
Someone said that some people who started threads had taken the habit of thanking everyone in a succession of posts (not the exact wording) and I think it will be a good thing to bundle all of the "thanks" in one, although I did prefer the previous way of doing things on regular threads.
It is OK for the Marketplace though.
JP