Unity panel service unexpectedly starts using 100% of CPU while panel applet menus become empty and transparent (could not take screen capture because the system was not usable). I don't know what causes this to happen as it happened to my only twice so far, but it might be something with LibreOffice Writer as I was using it both times (I don't have LibreOffice global-menu).
After some time CPU usage drops and system becomes usable.
ProblemType: Bug
DistroRelease: Ubuntu 11.10
Package: unity-services 4.22.0-0ubuntu3
ProcVersionSignature: Ubuntu 3.0.0-12.20-generic 3.0.4
Uname: Linux 3.0.0-12-generic x86_64
NonfreeKernelModules: nvidia
ApportVersion: 1.23-0ubuntu3
Architecture: amd64
CompizPlugins: [core,bailer,detection,composite,opengl,decor,snap,regex,resize,vpswitch,animation,move,compiztoolbox,imgpng,mousepoll,place,gnomecompat,wall,grid,workarounds,fade,unitymtgrabhandles,expo,session,scale,ezoom,unityshell]
Date: Sat Oct 15 11:58:06 2011
ExecutablePath: /usr/lib/unity/unity-panel-service
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Release amd64 (20111012)
SourcePackage: unity
UpgradeStatus: No upgrade log present (probably fresh install)
Status changed to 'Confirmed' because the bug affects multiple users.