There is good news and not-as-good news with Preview running on Mac OS X Mountain Lion. At the Betalogue blog, Pierre Igot reports that he has been annoyed for a long while by Preview's default "Continuous Scroll" setting when opening a PDF file for the first time. Many of us, Igot included, would rather see the view as single letter-size pages, which I would add is often the way that the document was originally formatted.
In Lion, there was no way to change this default setting. When you opened a PDF document for the first time, you could use a toolbar button to switch to the “Single Page” viewing option and then save the PDF with that setting, so that it would remember it the next time you’d open it. But still, it was a significant annoyance to have to do this once for each and every new PDF document.
However, after upgrading to Mountain Lion (OS X 10.8), Igot found that the button was removed and replaced with a pop-up menu. Not as convenient as before.
Digging around, he discovered a new preference that lets users decide between Continuous Scroll, Single Page and Double Page settings when opening a document for the first time.
Like Igot, I don't understand why some of these buttons are removed. They aren't overburdening the user with a wide array of buttons. At least, Apple should make this feature a part of the customization options for the toolbar.
In another recent post, Igot describes issues with the More Info part of the Inspector window. He says that previous problems with Column View in Lion have been fixed but not in the Inspector. If you use the Inspector frequently, check it out.