From the message listing I can see the total number of replies and in the column next to is I see the number of new replies. Lets say the number of replies for a particular topic is 58 and the number of new replies is 21. After browsing to the topic how do I know which replies are new ?
The old forum used to put a red "bullet" next to the new replies and you had to "scroll" the page to find the new posts. Using that method was a bit funky, in that the red bullets were sometimes difficult to see when you were scrolling to find those replies. No matter how terrible to use, it did work.
I don't see any way to identify it. You can go directly to the last post from the message list. But no way to identify any but the last.