Not a very Xoops-specific question this time, but anyway: Is access to post comments to articles and topics in discussion forums, in general a great enough incentive for most visitors for letting themselves get registered, or do a large (major?) part of the users prefer to stay unregistered on most sites?

What do you believe is the best policy: To keep as much fuctionality of the site available for registered users only in order to motivate visitors to register, or will such an approach make the site uninteresting and unattractive, causing less traffic?

I prefer to lurk on a site, unless I have a question or a constructive comment. Then I will register on the site to post that question. From an administration side, I prefer leaving anonymous access on nearly everything, but force registration before posting.