Here is what I did to try and duplicate the issue. Let me know if I am looking at this incorrectly.

Scenario 1:

• Go to the Flyertalk.com forum front page (http://www.flyertalk.com/forum/) and click on the 'Mark Forums Read' link near the bottom. This marks all the forums as read.
• Staying logged in, I close the browser.
• Open the browser and return to the forum front page.
• All forums are still marked as read.

Scenario 2:

• Go to the Flyertalk.com forum front page (http://www.flyertalk.com/forum/) and click on the 'Mark Forums Read' link near the bottom. This marks all the forums as read.
• Log out using the 'Log Out' button near the top.
• I close the browser.
• Open the browser and return to the forum front page.
• Log back into the forum.
• All forums are still marked as read.