The appliance is similar in some ways to IBM's SLES 10.2 based Informix virtual appliance, following the basic format of a pre-installed instance of IDS 11.50.xC4 Developer Edition, associated drivers and tutorials. You will see a few differences, such as tighter intregration with AGS Server Studio and other Bell Micro customizations.
To download the Ubuntu virtual appliance, and for more information visit Bell Micro's website at: http://www.informixcity.com/ubuntu.aspx
I like using Ubuntu and am very happy to see an Ubuntu based IDS appliance available. I find it to be one of the most accessible and easy to use Linux distros out there and get a lot of work done with it running on my old laptop (which IBM keep asking me to return, I'll do that any year now).