I got emerald almost working in kbuntu 7.10 now
I say almost becase for some reason The desktop selector thing in the kicker shows twice the number of virtual desktops than I have..
i.e if i have 2 it will show 4, even more oddly 3 is a clone of 1 and 4 is a clone of 2
Other thing I couldn't get working is the cube it doesn't seem to want to show it.
P.s if you manually start compiz you have to add a parameter to the command otherwise it won't acknowledge the setting from the settings app (and being on my laptop atm I can't remember what its called)