Considering that most Zope users are interested in most of these sites, except when the language is not english, and that some want to really participate, I think this registration process quickly becomes very boring, and remembering all the different passwords is difficult, unless you always use the same which is insecure.
Couldn't it be possible that all these servers share the same authentication mechanism, i.e. only usernames and passwords, and do all their local stuff on their own (roles, possible actions, homepages, etc...), in one word (ok, two) : Centralized Authentication
I think this is great idea. I also think that most people use the same username/password combination for these kind of sites anyway. Insecure as in that if you know my zope.org password, you'll know my zopezen.org password too (and probably my Slashdot one too), sure, but I only keep three sets of username/passwords and use them depending on the kind of site. Douwe