Pass on upgrade to Quantal Quetzal 12.10

I've been following the development of Quantal Quetzal in passive mode. I need the development release to maintain the Wubi move and resize scripts, so I don't have much choice in the matter, but I haven't been as involved this time around.

The most striking difference between development on Quantal and that on Precise Pangolin 12.04 has been the quality drop-off. Precise was remarkably stable throughout the development cycle, whereas 12.10 has had some rough patches, making it barely usable at times. Most recently I've found the zombie application window problem - which is when I've closed some applications but they still appear to be active - almost like an overlay on the desktop. In fact, moving to separate workspaces shows these zombie windows and even the launcher has the active window indicator. Now normally this isn't too big a deal - in development we expect some weird stuff - but it's very close to release, and what's more, this is a recent 'development' (as it were). So that doesn't bode well.

So what's really new with Quantal? What new benefits are there?
I'm having a bit of a problem figuring this one out.

• During development they renamed "Shut down..." to "Switch off..." on the system menu (but not the Shut down dialog pop up). Then they renamed it back to "Shut down..." a few weeks ago. 
• They've added the "Restart..." option back to the System menu that was removed in 12.04.
• They've combined the User and System menu into one
• The i386 non-PAE kernel has been removed so the PAE kernel becomes default on 32-bit installs
• They've added Amazon online search results to the main Unity search lens that ironically seems to return adult-themed toys for innocent search strings dynamically as you type. Because as everyone knows, sometimes you just randomly decide to buy things online when you're searching for documents on your computer.
• They changed some icons on the mail envelope a lot and then removed them
• There's no more live CD since the ISO is too big to fit on a CD. So you'll need a DVD or USB.
• There's no more alternate CD because support and testing two images takes too much time and they figure that the text installer is not needed anymore - and for those that do they can use the netboot ISO.
• There's a new version of Grub that supports UEFI secure boot (I believe this is on 12.04 as well)
• For Wubi, you won't be able to install Xubuntu anymore, but they have finally fixed the links for Kubuntu so that will be available and working.

Okay that was a list of nothing. What are the benefits?

Well, I really like the new blue sky wallpaper. And there are obviously lots of other little changes that may be important to users, like updates to more recent versions of some applications.

Upgrade Recommendation
I'd say pass on the upgrade unless there's something specific that you need. But bear in mind that if you decide to upgrade to 13.04 later, you'll still need to upgrade to 12.10 along the way.
Remember that there will be some new bugs introduced with the mainly cosmetic changes, added to the unfixed bugs from 12.04.
If you do decide to upgrade please make sure you have at least 3 GB free space - see here for more upgrade tips.

Wubi default
For new Wubi users, you'll be installing 12.10 by default from here. Get the wubi.exe for 12.04 from here instead if you prefer.

How to run the development release with Wubi

Prepare for breakage

This goes without saying, but I like to say it anyway. If you choose to follow these instructions, and you lose your installation/data or worse - you're on your own. That said, I've been running the development release on Wubi since 11.10 and with a few precautions you should be okay. 

Note: Since the 32-bit non-pae kernel will not be supported in 12.10, I advise not following these instructions if you are using the 32-bit non-pae kernel.

Backup and restore

Even though I am aware that things could go awry, it's still irritating to lose the install. So I keep a fully synched backup of the root.disk. After running updates (which you'll probably get used to doing every time you boot), once you've rebooted and confirmed things are stable, you can resynch your backup. 

Here's how to do it:

1. Make a copy of your root.disk using the Wubi resize script 
2. Keep it synchronized by rerunning the script, but supplying the --resume option (which will copy only files that have been modified/added and delete ones that have been removed).
3. Make the new.disk bootable (so you can confirm it works without booting to Windows to rename the disks). You do this by adding the following lines to /etc/grub.d/40_custom (changing the bits in red to match your own settings):

menuentry 'Ubuntu - backup new.disk' --class ubuntu --class gnu-linux --class gnu --class os {

        set gfxpayload=$linux_gfx_mode

        insmod part_msdos

        insmod ntfs

        set root='(hd0,msdos3)'

        search --no-floppy --fs-uuid --set=root 18B4B7BBB4B799A8

        loopback loop1 /ubuntu/disks/new.disk

        set root=(loop1)

        linux   /vmlinuz root=UUID=18B4B7BBB4B799A8 loop=/ubuntu/disks/new.disk ro   quiet splash vt.handoff=7

        initrd  /initrd.img

}

Then you'll see "Ubuntu - backup new.disk" at the bottom of the grub menu when you boot. If you don't see the grub menu, hold down the Shift key after selecting Ubuntu.

Upgrading to Quantal

Since there is no Wubi.exe version for Quantal available at this early stage of development, the only way to get it is to install 12.04 Precise Pangolin, and then modify your sources.list. (Note, once the Alpha1 is released you may be able to install normally and in this case you should not use this method).

sudo sed -i 's/precise/quantal/g' /etc/apt/sources.list

sudo apt-get update && sudo apt-get dist-upgrade 

Partial upgrades

Always review the results before running dist-upgrades. In particular, look at what is being removed. It's fairly common for the packages to be out of synch at times during the development release, and if you're not careful you might uninstall critical bits. My rule of thumb is, if anything is being deleted look for a newer version of it being installed. If there is no corresponding entry, then wait a few days. Sometimes you'll find the packages are no longer listed as being removed. In other cases, they're still there and it's probably safe to proceed. If you notice a lot of packages being deleted, run away.

Where to go for help

Please review the Sticky threads in the Ubuntu+1 forum on ubuntuforums.org. If you have any questions or problems, look there to see if someone else has a solution or post your own questions.