Cyberduck 4.5 is fully compatible with OS X 10.10.
With version 4.5 and later, notifications are displayed in the system taskbar on Windows. This applies to notifications when transfers have finished or a connection has been established or failed. It is most useful when editing files in an external editor application with a confirmation on screen that the upload has completed after saving the file in the editor. This new default behaviour can be disabled Control Panel → Notification Area Icons.