I really like the layout of Joomunity but there are way too many bugs right now, i installed but I am getting alot of javascript errors from jquery and there is an overuse of ajax. They are using jquery which has alot of conficts with joomlas 1.5 mootools.
I created a component a while back that allows users to have a public profile page that was exact to myspace, I guess i will have to do the same to make one like facebook.
what I have done is not creat a component that rivals CB but works with it. technically speaking all a person needs is a public profile page that takes info from cb database.
to see a hack that i created for a myspace type profile go to totalracefans.com