The settings have been made easier to manage and navigate in by being redesigned in a single consistent way. The setting panels for albums and categories have been replaced by setting pages which are very much like the Control Panel page, but with the respective settings for albums and categories. The settings are not only easier to navigate within, they also take up the whole page and are more usable and accessible than ever before.
The visitor registration settings can now be set for categories as well as albums and the whole account. The registration settings have also been simplified in there being only one form now - the settings simply change the display mode to either of : optional, mandatory, not displayed. Even when not displayed anywhere at all before the content is shown, you can still link your registration form from your custom menu, or your custom header or footer.
You can also leverage the standard setting inheritance which is applied to themes and privacy modes. As an example, you can set the visitor registration as optional for the whole account, but some categories (and thus also, the albums within them) will have it mandatory, while some albums will not have the form displayed at all. There is a multitude of variations on the example. It all depends on what you need, but it is there when you need it.