Yup, we offer both options. Some sites aren't trying to be 'social', like this site. We want you to be able to register and get in as quickly as possible so that there's as few obstructions as possible before a sale. This is a great selling point for us, and many sites use this feature. We agree, these usernames aren't 'friendly', but that's why we also have the 'full user' setting where a user can set their own.
I realize you already read about this feature, but thought I'd explain some more. If you want to test that method of registration, check out our demo site (
sourcecoast.com/jfbconnect/demo). In 3.1 we'll have a setting to allow the admin not allow the user to change their email address on registration (force the use of whatever their Facebook email address is).
3.1 should have Zoo support (or at least shortly thereafter). We're excited about that integration, as it's a very popular request.
Hope this all helps answer your questions!