You can read more about it in the wiki
You can clone the repository typing:
git clone git://github.com/PabloCastellano/gnome-rss-applet.git
Yarssr is not a huge piece of code and so, I don't think I will find many troubles.
I will try to keep writing here how is the development advancing.
My final idea is to distribute it with gnome-applets, taking advantage that now I have an account in git.gnome.org :)
gnome-rss-applet in GitHub