“First of all, the Time Machine menu bar icon no longer rotates whilst performing a back up,” Harris reports. “This was handy as a visual way of knowing that Time Machine was in the process of backing you up, but in Mavericks, Apple want to hide things even more from the Graphical Interface so users don’t have too many distractions. If you need to know that a backup is being performed, the menu bar icon does very subtly change to have an extra Arrow in the clock face.”
Harris reports, “The second thing I have noticed that has changed since upgrading to Mavericks is that as I backup to a Time Capsule drive over the network, the Time Capsule Drive does not ‘Mount’ on the Desktop nor show up in the Finder Sidebar as before during a backup.”
Read more, and see the screenshots, in the full article here.