How is the scrolling in the Preview app when viewing PDF files? Is it butter smooth - 60fps? (it certainly isn't in Mountain Lion)
PS: I wish Preview also had tabbed browsing like the Finder in OS X Mavericks.
It's so smooth, you are advised to wear a seat belt else you may slide off the couch.
ML is perfectly fine for me. Me thinks it's just all the euphoria for anything new.