When browsing the forums, in the thread list you can go to the latest post by clicking on the little blue arrow way on the right next to the latest poster's username, underneath the "Last Post" column in the thread view page. Click on that arrow instead of the thread title to go to the latest post.
Or
Instead of clicking directly on the thread title, click on the blue down arrow icon to the left of the thread title, this will take you to the first unread post.
Hope that helps and makes sense.