The old animation was a must-have for those of us who fiddle with edges of pages when reading physical books. Only method of ebook reading I've seen that satisfied that particular I-suspect-uncommon-but-not-rare book-reading behavior. Not the same as running a finger over the corner of the whole block of pages, but close enough.
However during the transition the text is sometimes obfuscated by a huge white space that doesn't exist on a real book that is indeed recto/verso printed.
It's fun for fidgeting but I personally find it way more visually distracting than the new behavior.
