So Ubuntu 11.10, Oneric Ocelot, has been released. I have now taken the plundge, or pludge, as some might say. So far I saw only one error while upgrade. So far, looking around it appears that 11.10 is a incremental improvement over 11.04. I'm still double-checking everything, but it appears this is an easy and smooth upgrade...!

The problem I encountered was :

Setting up dictionaries-common (1.11.5ubuntu1) ...
update-default-wordlist: Question empty but elements installed for class "wordlist"
  dictionaries-common/default-wordlist: return code: "0", value: ""
  Choices: , Manual symlink setting
  shared/packages-wordlist: return code: "10" owners/error: "shared/packages-wordlist doesn't exist"
  Installed elements: american (American English)

  Please see "/usr/share/doc/dictionaries-common/README.problems", section
  "Debconf database corruption" for recovery info.

update-default-wordlist: Selected wordlist "" 
does not correspond to any installed package in the system
and no alternative wordlist could be selected.
dpkg: error processing dictionaries-common (--configure):
 subprocess installed post-installation script returned error exit status 255
dpkg: dependency problems prevent configuration of xscreensaver-data-extra:
 xscreensaver-data-extra depends on dictionaries-common; however:
  Package dictionaries-common is not configured yet.
dpkg: error processing xscreensaver-data-extra (--configure):
 dependency problems - leaving unconfigured
No apport report written because the error message indicates it's a follow-up error from a previous fai
lure.
     Errors were encountered while processing:
 dictionaries-common
 xscreensaver-data-extra
E: Sub-process /usr/bin/dpkg returned an error code (1)

This appears to be a problem with dictionaries-common being corrupted. Apparently, you can see the dictionaries installed by performing:

echo metaget shared/packages-wordlist owners | debconf-communicate

This gave me an error:

debconf: DbDriver "passwords" warning: could not open /var/cache/debconf/passwords.dat: Permission denied
10 shared/packages-wordlist doesn't exist

Reading further, I found that dictionaries can be reset via:

sudo /usr/share/debconf/fix_db.pl

I then had another look at my installed dictionaries, and this time I got:

josh@home@:~/$ echo metaget shared/packages-wordlist owners | debconf-communicate
debconf: DbDriver "passwords" warning: could not open /var/cache/debconf/passwords.dat: Permission denied
0 wamerican

Then to fix apt, I did:

sudo apt-get install -f