Ubuntu fail (and fix): After the latest "update," unity crashes on alt-tab

I love ubuntu linux -- as loyal a user as they come -- but I still have to share this horror story.  It's a good case study in the ups and downs of working in a fully open-source environment.

Last week, I installed routine updates to ubuntu on my main work computer. Unfortunately, there's a huge bug in the latest update: switching windows using alt-tab crashes Unity, the main GUI for ubuntu 11.10.

This makes it impossible to open new applications -- or even shut down without holding down the power button. It also disabled keyboard input to the terminal -- like severing the spine of the OS.  Since alt-tab is a deeply ingrained reflex for me, the "update" made my computer almost entirely unusable.

For the record, this is by far the biggest bug I've run into so far with ubuntu.

The bug was reported early on, but I don't know how long it will take to fix. After four days, the status was "critical, unassigned," which I take to mean "we know it's a problem, but haven't got to it just yet."

In the meantime, I still had work to do.  I posted to various forums (like here), but didn't get much in the way of specific help -- unusual for the ubuntu community.  For the most part, I worked in a campus lab (which brought its own problems: missing software and no admin rights -- the reasons I'd come to rely on my laptop so much.) When I absolutely had to use my laptop, I sat on my left hand to avoid the temptation to switch between windows via the keyboard.

Today, I finally knuckled down to finding a workaround on my own.  It took me about an hour to discover gnome-shell, the major competitor to Unity.  From there, installation and configuration took less than 10 minutes.  I don't like gnome's look as much as unity -- too much chrome -- but if it makes my system usable, I'll keep it.

Here's the site that gave straigthforward installation instructions for gnome-shell:
http://www.ubuntugeek.com/how-to-install-gnome-shell-in-ubuntu-11-10-oneiric-ocelot.html

Here are some other links that were helpful, but probably not necessary for the final fix:

• http://askubuntu.com/questions/29553/how-can-i-configure-unity
• http://ubuntuguide.net/classic-menu-indicator-update-added-system-settings-menu 
• http://ubuntuguide.net/classic-gnome-style-menu-in-ubuntu-11-10 
• http://bloggezmoy.com/2011/05/17/how-to-add-an-application-to-the-gnome-3-application-launcher/

Also, there was a brief time where I disabled unity, but didn't have gnome running yet.  This meant that my only way to launch applications was from the terminal.  Here are some commands that will save your sanity in this situation:

• Ctrl-Alt-T : Load terminal, from anywhere.  If you turn off unity, this is the only way to launch new programs.
• firefox &  : Load firefox from terminal.  Now you can get online for help.
• gnome-session-quit : Now you can log in and out.
• shutdown : Now you can shutdown without yanking the power cord.