For the most part, I think I will get used to the new forum layout and like it better than the previous version. However, having to mouse over something to see the timestamps of the "Active Discussion" section and the most recently updated topic in each forum is pretty annoying. If that is configurable, I recommend changing it back. If it is unavoidable with this version of YAF or perhaps whatever theme is in use, I'll go find their support channels and report it as a UX regression there.
Also, the browser tab title of any thread I have opened to read seems to become "1 new message" whenever the tab or browser window is first opened or un-hibernated - it changes back to the thread title after the tab has been activated, which is not very helpful, since that is usually also after I want to be able to tell which thread it is by mousing over the tab.
I think that is being caused by the tawk.to widget. If not, I presume it's from the forum, in which case it is both annoying and inaccurate, because it always says 1 new message no matter how long the thread is or how much of it I have already read. If this issue can't be remedied, I shall most likely report it to tawk.to as a bug - but their own website doesn't seem to have the same issue, so I am inclined to think either I'm wrong about it being the culprit or it can be fixed.