Filing this against xorg initially as I'm not sure if it's related to the driver or if it's a Unity bug, though I've not seen this behaviour on other systems.
Plugged an external monitor into the Thinkpad T510 (7375) using the DisplayPort port. The external monitor DID come alive and display at least the 11.10 background, but Unity crashed (panel, launcher and window-decorations all went away). I had to drop to a console and reset Unity to get all the controls back and working.
Tried this twice and same thing happened each time. Plug in DisplayPort, Unity, Window decorations, Launcher all disappear even though external monitor comes on (also with no panel). unity --reset at console after unplugging external monitor to fix.
I'm also attaching a short video showing this as it occurs.
ProblemType: Bug
DistroRelease: Ubuntu 11.10
Package: xorg 1:7.6+7ubuntu7
ProcVersionSignature: Ubuntu 3.0.0-12.20-generic 3.0.4
Uname: Linux 3.0.0-12-generic i686
.tmp.unity.support.test.0:
ApportVersion: 1.23-0ubuntu3
Architecture: i386
CompizPlugins: [core,bailer,detection,composite,opengl,decor,mousepoll,vpswitch,regex,animation,snap,expo,move,compiztoolbox,place,grid,imgpng,gnomecompat,wall,ezoom,workarounds,resize,fade,unitymtgrabhandles,scale,session,unityshell]
CompositorRunning: compiz
Date: Mon Oct 17 11:26:10 2011
DistUpgraded: Fresh install
DistroCodename: oneiric
DistroVariant: ubuntu
ExtraDebuggingInterest: Yes, whatever it takes to get this fixed in Ubuntu
GraphicsCard:
Intel Corporation Core Processor Integrated Graphics Controller [8086:0046] (rev 02) (prog-if 00 [VGA controller])
Subsystem: Lenovo Device [17aa:215a]
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Release i386 (20111012)
Lsusb:
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 002: ID 8087:0020 Intel Corp. Integrated Rate Matching Hub
Bus 002 Device 002: ID 8087:0020 Intel Corp. Integrated Rate Matching Hub
MachineType: LENOVO 43492LU
ProcEnviron:
LANG=en_US.UTF-8
SHELL=/bin/bash
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.0.0-12-generic root=UUID=6ebbd55b-cdb1-42ff-8d08-89305e566190 ro quiet splash initcall_debug vt.handoff=7
SourcePackage: xorg
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 02/09/2011
dmi.bios.vendor: LENOVO
dmi.bios.version: 6MET82WW (1.42 )
dmi.board.name: 43492LU
dmi.board.vendor: LENOVO
dmi.board.version: Not Available
dmi.chassis.asset.tag: No Asset Information
dmi.chassis.type: 10
dmi.chassis.vendor: LENOVO
dmi.chassis.version: Not Available
dmi.modalias: dmi:bvnLENOVO:bvr6MET82WW(1.42):bd02/09/2011:svnLENOVO:pn43492LU:pvrThinkPadT510:rvnLENOVO:rn43492LU:rvrNotAvailable:cvnLENOVO:ct10:cvrNotAvailable:
dmi.product.name: 43492LU
dmi.product.version: ThinkPad T510
dmi.sys.vendor: LENOVO
version.compiz: compiz 1:0.9.6+bzr20110929-0ubuntu3
version.libdrm2: libdrm2 2.4.26-1ubuntu1
version.libgl1-mesa-dri: libgl1-mesa-dri 7.11-0ubuntu3
version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
version.libgl1-mesa-glx: libgl1-mesa-glx 7.11-0ubuntu3
version.xserver-xorg: xserver-xorg 1:7.6+7ubuntu7
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.6.0-1ubuntu13
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:6.14.99~git20110811.g93fc084-0ubuntu1
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.15.901-1ubuntu2
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:0.0.16+git20110411+8378443-1
Here's the promised video showing the failure in action as I plug in the DisplayPort connector.