Thread view lists every post in outline form, so that you can mouse over any post and see a preview.

List view allows you to see only the title of each thread, saving screen space, and also allows you to go directly to any page in a multi-page thread.  

You may want to try both to decide which you like better.

To change from one to the other:

1. Find the dropdown menu box called My Menu in the upper right, right below the 7-Day Free Trial offer box.

2. Click on My Profile.

3. Click on Edit My Profile.

4. Under the Topic View dropdown box, select Thread View or List View.

Voila, you are done.