From Michael Scrivo:
Outlook on the Desktop organize our daily lives have them visible in plain sight nearly all of the time. Yet, on your PC, you have to go through a myriad of windows and clicks before you can even see your calendar. The calendar object gets pinned to your desktop and stays there all the time in plain sight so you can always see what's upcoming.
What's new in this version:
Version 2.1.3 fixed an issue where OotD would crash on windows startup if the Windows RPC server was not yet available and added a message to let users know if they've installed the wrong version.