Getting 9 screens is easy enough once you can find the instructions. Just install Matan's modified hildon home and enter this code in terminal (as root):

gconftool -s /apps/osso/hildon-desktop/views/active -t list --list-type int [1,2,3,4,5,6,7,8,9]

See more instructions in this link (seems overly complicated but at least you get some pictures of some really hot desktops).

http://www.lookatbowen.com/2010/10/h...our-nokia-n900

Also I seem to remember the maker of Desktop + this week posting where to find the app now. Don't know which thread it was, maybe search for the Desktop + thread.