So, since I upgraded to Jaunty, I had been seriously irritated with their decision to change the way updates are handled.
Instead of the familiar update notification icon in your notification area, the update window just pops up when a security update is available, or once a week for everything else. I'm not running OS X or Windows. I'll update my computer when I feel like it!
Fortunately, I was looking at the Jaunty release notes for an explanation of this idiocy, and instead of finding good reasoning, I found a way to change it back to the old behavior.
gconftool -s --type bool /apps/update-notifier/auto_launch false