It resets when you close the browser.
I guess it has to do with the recent database switch thingamajig, but that's pretty much all I know :v
Actually posting here to say that I can not see the name and other data of the user who posted this reply.
I guess an image describes this better than I could with words:
Look at dat 'Last seen' and wow, that person made 3227 posts in 0 seconds since I opened that page!
Your layout has been removed.