I agree with rabidcow. I usually browse through ls.net a couple times a day during work. if I get called away for something, I don't always(or even usually) remember to set the page to refresh every 5 minutes (just one of the things I love about opera ;) ). then I get back to my computer, and, of course, I've been logged out. going through each post, and looking at the last time anything was posted to it takes more time than just looking at the thread's icon color to see if it was read or not.
there has to be some way of logging which threads have been read, and then resetting that whenever the threads are posted to, on a per user basis, instead of a per logon basis.