How to change handler of APT: URLs?

In Firefox on a fresh install of 10.10 when visiting apt.ubuntu.com/p/banshee (for example) I get prompted with the following window:

However, I was under the impression that apturl was supposed to launch Software Center. How can I configure what application apturl is launched with - and is the above screenshot expected actions for 10.10?

Solution 1:

Yes, that is the default action.

This can be overridden by Firefox, but out of the box the gconf setting
/desktop/gnome/url-handlers/apt/command is used. By default that command is apturl "%s".

You can change that by using either using the graphical tool gconf-editor or from the command line:

gconftool --set --type=string /desktop/gnome/url-handlers/apt/command 'software-center "%s"'

This will make Software Center handle apt URLs.