when I return from previewing a post, about one-fifth of the time the paragraphing is blown away and I'm faced with one huge block of text that I have to re-format. Usually, the title is gone, too. Today the entire post disappeared after I previewed it.
Yes, I saved before I previewed.
Bring back the old "Save and Continue Editing"! It was far easier to use, and at least I always knew what was going on. Now, writing a post is like dissecting mystery meat - I don't know what I'm going to get, or find.