I recently upgraded to Plasma 5.2 based upon this glowing review. While the transition was smooth for the most part (apart from minor KWin issues), Vidyo started to segfault. The Plasma system tray no longer supports older system tray protocols. I'm not aware of the details, but VidyoDesktop would complain about not being able to set a system tray icon and segfault. The fix is to install the sni-qt package from the extra repository.

http://blog.nikhilism.com/2015/02/getting-vidyo-running-on-archlinux.html