[thelist] How to display data correct semantically

[Kristina Floyd]

Hello listee's

I have a semantics question for you.

I have a message board that I am creating the prototype HTML pages for.

<http://24.m-corp.com/id20-discussion-bd.jpg>
The first page of the discussion board displays all the top level topics
plus the name of the person that posted the topic, the number of posts
and the date of the last post.

<http://24.m-corp.com/id21-discussion-bd.jpg>
When the user clicks on the topic he/she wishes to view a second page
opens showing a list of the replies to the topic, each indented a little
to show it is a reply to the one above.

Now my question is this - at the top level without any of the replies
visible the data is tabular.  at the second level with the replies
visible the data continues to be tabular but is also a list as well - -
or is it?

How should I mark it up so that it is correct?

Tia
Kristina