running now on the iMac with everything working ...

I'm seriously tempted to upgrade from Ubuntu 11:10 to Kubuntu 12:04.

I've tested it via a live usb and it runs great and looks lovely.

just finished setting everything up and will keep playing with it but its working at a rate of speed that is impressive
and the reason i waited to install this on the iMac was for the 5 years support ...

reinstalled Kubuntu 12.04 LTS as i wanted the partition sizes changed, having a 8GB swap file with the default install was far too large

set it up thus ...
20GB / (root)
2GB swap
rest of HDD /home
all set as separate partitions

also setup a full root account so now am able to login to a full root account (no sudo)
somethings still work better using a full root account and is very easy to set up
for day to day usage i have and use a user account but am able to fire up the root account if needed

also to update Java with deb packages for the system have a look at this howto
http://www.duinsoft.nl/packages.php?t=en

apart from the internal speakers not working, at the mo (using usb logitech speakers), everything is flying along ...