Plinth provides the front end for other software.
Mathieu Jourdan's modified Plinth is available at http://wiki.debian.org/FreedomBox/UserInterface?action=AttachFile&do=view&target=FreedomBox_bootstrap_milk.png
The FreedomBox visual list will influence the appearance.
To fork and make those changes in the Plinth templates:
- git://git.tuxfamily.org/gitroot/plinth/plinth.git (for milk changes)
Making Plinth *actually do stuff* is one of the beta-release goals. This may be tackled at the second Hackfest.