What are the pros and cons about letting non reg memb view the content in the forums?

[Allnick]

My thoughts are, if I allow everyone to view the forum's content, they will find no need to register.
If it's interesting enough they will register.

Denying access to visitors is a definate NO. If they can't see the forum , how can you expect them to be interested enough to join?

My forum is viewable by anyone...and has 2000 plus members.

Also, if you restrict it to members only, you also deny the search engines access to trawl and index your site.