We at spottiness.com are very interested in this line of work. I can see the appeal of the simplicity of the solution you propose. On the other hand, in many cases the invitees would prefer to not have their emails associated with their comments anywhere (your service would have that information internally). That is an interesting problem.
just to clarify, we don't associate emails with individual comments even in our backend. Emails of those invited appear at the top of the discussion page. Each comment can be posted independently of whatever email is up there.
dbs11, do the emails appear in any given order? You may want to be sure the order is randomized, otherwise the person who starts the group might be able to figure out who is who rather trivially.
that is definitely true. I think a major part of developing this type of discussion space is generating user trust. Besides trusting us, we also need users to trust each other, to keep comments responsible. It's a big task no doubt.
