I agree it's a little disconcerting with the go to first unread post links now gone.
However, clicking the thread title has always, and continues to, bring you to the first unread post!
If anything there is just a little less visual representation of what is read and unread. Clicking watched threads now shows both instead of a list of only unread watched threads, which was more convenient.
But I'm giving things a few days because I have a feeling these are changes you will get used to.