Hi Mike,
When I started the forum I took the decision that being able to find a forum member was more important than finding the most recent member, so I have always pinned the "Introduce Yourself" posts in alphabetical order. To re-do that to show entries in date order would, at this stage be a mammoth task. However, I do accept that without doing that it does make it difficult to find recently joined members.
If monitoring new members is important to you, the best thing to do is go to the
Introduce Yourself page and then select:
Options > Subscribe via email
and on the following screen select "New Topics Only". That way you will receive, by email, a copy of any introduction as it is made - but will avoid receiving any responses to that introduction.
If you do do this, then I would encourage you to use the link in the footer of the email to reach the post on the forum, rather than using the "reply" facility in your email program.
(Too often people top-post their email replies, and that generates duplicate content, - very annoying to forum users when a one line response is given over a long post - and it upsets search results, as frequently the reply will show up in advance of the original post in results listings.)
On the forum itself, the best you can do is go to the top level of the forum and switch to "Topics View". This shows all posts in the forum in date order. The sub-forum in which any post was made shows shows in the right most column, so you need to scroll down the list until you see a post made in "Introduce Yourself" listed. Of course, even that does not show you when the most recent member joined, but only when the most recent post was made relating to that introduction, and it could be that someone suddenly notices something interesting in the introduction and posts a response months later.