it is really frustrating, it never logs out on IE but on Firefox it still boots me. If you google phpbb and cookies, you can see it is a huge issue. Hopefully we will hit our donation goal soon and migrate to a supported commercial platform and a lot of these issues will go away.
I personally am excited for the blog capability, so those particular users who like to have a 10 page running post to blog, can do it in a more "formal" blog setting ... I think it will be exciting.
Derek