There are several possible reasons for this:
- You have configured Remote Buddy to only appear in the dock.
- Too many tools on your system occupy title bar space with their symbols not leaving any space for the system to also display Remote Buddy's symbol. Quit these tools to regain access to the Remote Buddy icon. Due to a bug in OS X, you may have to select different application's windows before the titlebar layout is refreshed (i.e. click on Mail, then on the Finder to trigger a relayout).