This has been a problem for a long time. I went out, got some food, came back, opened up my browser and dozens of threads that I've already visited show up as "new". Even ones I'm the last one posting in. This of course affects my ability to go to the newest post on a regular basis. In some cases (the Jesus last name thread) it will send me to the last page when I click on newest post even though I haven't seen several pages worth of posts. I'm using Firefox but I'm pretty sure it happened when I used Chrome too.