Like the PC version, Kindle for Mac is a bare-bones reader. You turn pages with either the scroll-wheel of your mouse or the arrow keys, and it stays in sync with any other device authorized for the same account. You can view notes and bookmarks made on other devices, but you can’t create new ones (a limitation shared with the PC version).
change font size from very small to very large, allowing those who may have had difficulty reading a standard book font the ability to enlarge it for easier reading
Basic article on libraries using ereaders. Some insight into managing multiple ebooks across devices. Wish there was a good resource to explain the how-to aspects of management.