The bar along the top of the form editor had grown to five things at once, including two different ways to look at the same form.
There is now one. While a form is still a draft you get Preview, because a draft is the only version there is. Once it is published you get View form, which opens the real thing at the address you would give to someone else. Publishing a draft swaps the button over straight away.
Responses has moved to Form settings, where it sits alongside everything else about a form that is already out in the world. It is still on the forms list too.